The Chimney Sweep Online Fireplace, Woodstove, Gas Stove and Barbecue Shop

Letters From Vent-Free Gas Fireplace Owners

Sweepy If you're considering a vent-free gas appliance, you should first read these letters, excerpts and E-mail postings written by vent-free owners. We've corrected spelling and grammar where necessary, and edited out some of the harsher language from the original text.

# 1: Serious ongoing health problems

My Name is Kim, I am trying desperately to locate other people who have suffered the long term effects of CO. My Family of four was poisoned for over two years, before we found out why we were all so sick. My five year old daughter was having many illnesses, eventually led to seizures. This all stemmed from a ventless gas fireplace we installed in our basement. Three months after it was installed my daughter had her first seizure. Husband began having severe headaches, trembling, memory loss, and numerous other ailments. Neurologists diagnosed daughter as epileptic!!!!! They now know they were wrong.

This began in January 1995. Husband still on oxygen every day, and medication, and extreme memory loss, and other problems. Daughter is having no more seizures, and last EEG done three months after gas shut off, was normal. First normal EEG in two years. We have been through it all!!! If anyone knows about CO, it's me and family. I have found a support group based in the United Kingdom that is helping us deal with this mess. And we are in search of other people who need our help. We are also trying to find a way to inform the public about this silent killer. Would you be able to help us in any way? Your concern could save a life. We have had a forensic scientist in our home doing tests on fireplace, and the final result was determined that you cannot put a combustible gas in an airtight home and not vent it. I have done much research on this situation and talked to toxologists, chemists, and other specialists, and not one of them can believe we are still alive, they are all behind us all the way. I'll be waiting to hear from you.


#2: Headaches, dizziness, unacceptable CO levels
Date: Monday, March 30, 1998

We are a young couple with four children and live in a small community in Ohio. In 1996, we built a new home and moved in in late October. In November, we decided to try out our new vent free gas fireplace. Neither myself nor my husband are familiar with gas appliances, so we called [the owner of the retail shop where we bought the unit]. He had what he called a startup package for around $40. We were surprised at the charge since nothing was mentioned at the time of the sale, however we decided it would be best to know how to use it properly.

We asked [our retailer] about using a CO detector. He told us they really aren't necessary because the unit has a built in sensor that will shut itself off if the level gets too high. He also told us to let the unit burn for 4 to 5 hours to get the initial smell and burn off from the logs. We did this, but still noticed an odor even after 10-12 hours. We called [our retailer] again and were told to burn the unit for 100 hours. This seemed extremely long, but we did this over a series of 2 months.

In early January, we were still experiencing the odor and also seemed to notice a listlessness in our children, dizziness and sometimes headaches, while running the unit. At this time we still did not have a CO detector, so we have no idea how high the reading got at this point.

We finally decided to go out and buy a CO detector. Within half an hour of turning the unit on the warning alarm sounded. We called [our retailer] again and now he says that these detectors warn you way before there is a problem, so he still says we do not have a problem. We decided to buy another one and have one on the first and second floors. The upstairs would alarm within half an hour and the downstairs within 2-1/2 hours.

Again, we contacted [our retailer] and he told us the CO detectors we bought are too sensitive and to call [the manufacturer], to see what they recommend. They recommended a different brand with a digital display. So, we go out and buy our third CO detector. We now have two different brands of CO detectors in a loft area overlooking our great room. The great room measures 17x20 and has a 17 foot cathedral ceiling and this is where the vent free fireplace is located. The great room is also open to a kitchen/dining room and a 2-story entrance. So, it is a very roomy and open area. The following is an example of one days CO level readings:

  Time          Reading                Description


 7:50 am           0                Turned fireplace on

 8:05 am           7

 8:20 am           9             Upstairs CO detector alarm

 8:45 am          11

 9:40 am          13

10:15 am          14            Downstairs CO detector alarm

10:50 am          15

11:20 am          16

12:00 pm          17

12:30 pm          18

 1:20 pm          19

 2:00 pm          21                 Noticed dizziness

 2:20 pm          22

 2:45 pm          23          Headache starting - turned unit off

It took until 8:00 am next morning to get the detector reading below 10. These levels are not considered very high, but being exposed to these on a daily or every other day basis which we were in trying to get this 100 hours of burning time in, may become harmful, especially for our young children.

On another day of recording the readings, we got the following results:

  Time          Reading                 Description


10:00 am           0                Turned fireplace on

11:05 am          10

11:45 am          12

12:25 pm          14

 2:00 pm          20                Turned fireplace off

We called the fire department out and they felt we had a problem and should call the gas company. The gas company came out and they too felt we had a problem. Their representative told us any reading over 10 is unacceptable in a residential home. He also told us he was "red flagging" the unit, which he explained to mean that he had checked out all other possible sources of CO and determined the cause to be the vent free gas fireplace. This would let the gas company off the hook if something would happen to any of us.

Throughout this whole process we had over 30 phone calls to [the manufacturer] and [our retailer]. [Our retailer] was not willing to do anything except tell us to talk to the manufacturer. [The manufacturer] did try replacing the logs, they tried replacing the whole guts of the unit and the logs. The old unit was then to be sent back for testing. [The manufacturer] instructed [our retailer] to install the new burner and logs and return the old unit. I checked on the results of this and every time I was told that they had not received the unit from [our retailer]. They also tried new brick panels too. We still got the same results and every time they sent something new we had to go through the initial burn off process again.

Finally, after one year of frustration, [the manufacturer] suggested we try something new called a catalytic converter unit. They were going to send out technicians to check out the other unit and install this new catalytic converter unit. Well, here's another problem. We have the old unit enclosed in a brick front that goes all of 17' in height. I do not want to have to go through the expense and the mess of having the old one cut out and then the new one put in and still have the possibility of having problems because it would still be an unvented unit. We have done too much research in the meantime and know that we want nothing but a vented unit that has a vertical pipe running all the way up and through the roof. We only wish we knew all we do now before we started building. We are going to go through the expense and the mess and have this unit replaced, but we want nothing to do with any gas appliance that is unvented.

We have since this time talked to several people in fireplace sales and gas appliance installation and none of them are recommending the vent free units. We sure would not recommend one. We only hope that this information may persuade a person who is thinking of buying a vent free unit. Please think twice about it because we have also had moisture problems as well. Which is a totally different story.


#3: Soot all over the house
Date: Thursday, October 14, 1999

Hello, Found your webpage..and was so thrilled..have some questions. We purchased a vent free fireplace from a local distributor 2 yrs ago, and it has been nothing but a nightmare...soot, soot and more soot. I have been told it is the fact that it is vent free, or it is [the manufacturer]...whatever...they have not been able to fix the problem. So we have a beautiful fireplace I won't use, because it ruins the walls, curtains, etc. We have decided the only solution to our problem is to go with a vented fireplace, but will not buy from the same folks, and are very skeptical about buying thru a place like Lowes, etc. This can be a costly addition, and we don't want to have to go thru this repeatedly. Our source of fuel is propane..we also use this with our furnace. We have decided we'd better go to a vented fireplace, so am looking for suggestions. The fireplace we have now says max. 22, 000 btu, if that will help with size, etc. I would appreciate your assistance.
Thank You.



#4: Massive condensation damage
Date: Monday, May 15, 2000

Despite a science background, I failed to consider the water production from burning propane when I left the (installed by builder) vent free wall gas heater on (low) in a mountain cabin during winter months to thwart freezing and supplement electric units. Well the pipes didn't freeze, but all windows had enormous ice deposits along their base and sides from the thaw/drip/freeze of condensed combustion water. This damaged drywall around the windows, cracked a large picture window (several hundred $ repair), and required me to strip and refinish water-damaged sills.

Even worse, the moisture condensed on the underside of the (poorly designed) sheet metal roof, whence it melted in spring to anoint the upstairs ceilings and floors with dripping drywall coatings and stains. This led to the belated recognition of the need for roof rebuilding (couple kilobucks) to help prevent future condensation, and the epiphany that non-vented gas heaters are bad for the house's health even if acceptable for the occupants'.

While pleased with myself for tracing the problem to the heater (I calculated how much water would be produced by the amount of propane consumed that winter while laying awake worrying about the demise of the house), I sure wish someone had educated me about the hazards beforehand.
Frank Symington


#5: Odor, dizziness
Date: Saturday, Feb 24, 2001

The only thing we do not like is that we feel very sick when using [a popular vent free model] even after letting the initial use take place. We're sure we let the initial odors and factory smells burn off, but it still has a dizzying effect on us. The dealer didn't help us much after we told them. I think we'll try and contact someone at the company to see if we can trade it in for a vented unit.
Posted at


#6: Wish they had bought a vented stove
Date: Monday, Feb 25, 2001

[A popular vent free model] needs to be in a house with lots of air holes. If fumes bother you. I sort of wish I had paid a little more and got a vented stove. My house is a little too tight or small for a vent free one.
Posted at


#7: Hearth product retailer has removed over 200 vent-frees
Date: Wednesday, April 11, 2001

I can't believe ventless products are still on the market. My company has removed over 200 vent free products now and replaced them with direct vents.The problem with this vent free issue is it's going to hurt the whole industry.When people come into our showrooms with problems, they don't say "my vent free product caused the problem" they say "my gas logs or my gas fireplace caused the problem". This is an area that we'd better start looking at as a industry.
Perry Bumpers


#8: Hearth product manufacturer refuses to offer "lung vented" products
Date: Thursday, April 12, 2001

I ran across your site yesterday when searching under "vent free". What a refreshing breath of fresh air to find a dealer who "gets it" when it comes to lung vented products! As you know, we (Heat-N-Glo, Heatilator and Aladdin) will not manufacture room vented products for the very reasons detailed on your website.
Tim Rethlake
Vice President, Business Development
Hearth Technologies


#9: Soot damage
Date: Tuesday, April 24, 2001

Just thought you would like to know that I am currently the unhappy owner of a vent free fireplace that has sooted up my entire house. I just completed building the house this past spring, and heated it with the ventless almost exclusively this past winter after receiving a $600 electric bill after heating with my furnace for one month. Initially, the ventless fireplace seemed like a godsend.

After a couple of months, however, we noticed that the ceiling edges were beginning to collect soot. Shortly thereafter, all of the ceiling joists, wall studs, and drywall nails began showing up due to soot highlighting. We are now working with our insurance company to determine whether the cause is moisture in the gas or some failure in the ventless fireplace system. Regardless of the cause, all the walls and ceilings in our new home now looks black and dingy. Insurance will pay to have them washed and repainted, but in the meantime, the place is a mess.
Walt Guntharp


#10: Can't live with vent-free
Date: Thursday, August 2, 2001

I currently own a vent free fireplace in Orlando and am in negotiations with my home builder over it. We can't live in the house when it is on! He is offering to return some of the money paid for it and remove it and leave a useless space for the fireplace, or vent it. I think I want it vented, with glass on the front and proof that there are no leaks. He cites two studies done by the manufacturer that say the fireplace doesn't have harmful gases and was built to code. But there is a terrible odor that causes your eyes to burn, throat to itch, and eventually you get a headache.
John Edvardsen


#11: Headaches, dizziness, noxious odor
Date: Saturday, October 6, 2001

I read your Q&A about vent-free stoves. I have a [popular vent free model], and for 2 years I've been trying to make it so it doesn't smell and give me headaches and dizziness. I don't leave it on for more than half an hour because I can't stand it, so leaving it on too much is not the problem. It is in a large room with lots of windows and an open hallway; the noxious odor goes upstairs, so I know the problem isn't ventilation or the wrong size space.

I've done the burn-off routine, and the shop that sold it to me gave me replacement logs, but the problem persists. After reading your site, I know I'm not crazy. The dealer will not take it back, and I'm done trying to make it work. Can you give me any info to get into direct contact with [the manufacturer]? There is no email address at their website. You have my permission to forward this to [the manufacturer] or post it on your Q&A page.
Marbet Wolfson
Exeter, NH


#12: Wife has headaches
Date: Thursday, November 29, 2001

Hello - We recently purchased a vent free gas fireplace for our home. My wife started getting terrible headaches when it was on. We stopped using it and turned the gas off to it and her headaches went away. Is there any way to properly vent a ventless fireplace or do I need to purchase a new one?
Clyde Myers

Sweepy Hi Clyde,
Unless your vent-free was designed with the option of installing an exhaust vent (some are), there is nothing you can do with a vent-free except replace it with a vented model.


#13: Vent-free manufacturer gets 100 complaints per day
Date: Saturday, December 15, 2001

I'm so glad I came across your web site. I purchased a propane vent free gas log set during 2000. I have been unable to use it because of the smell. I've made various attempts to correct the problem: I let it burn off, I followed the manufactures recommendation and burned it on high for eight hours, I opened the windows, I've done everything to get rid of the exhaust / C0 smell. Nothing works. I've had the propane company check the recommended flow rate / pressure rate, in fact I had two companies do it. No one has offered to replace the log set, the seller told me to contact the manufacture, the manufacture hung up on me when they couldn't answer my questions. The vent free set burns our eyes, makes us dizzy and affects our throats and noses. No one will tell you this, everyone I talk to tells me my set is unusual, normally they can't smell a thing.

When I called the manufacturer, I heard another operator telling the caller he gets a hundred complaints a day. I couldn't tell what the complaint were, but I'll bet it's the smell. I was told by the manufacturer, get rid of the candles, don't buy new carpet, don't use spray cleaner, don't paint, on and on.......Believe me, I will not operate my vent free system. I will, when I can afford it, purchase a vented unit.....And I didn't tell you about the moisture, film on the windows and the complaints from visitors.

So I'm stuck with a lemon, but others beware, I have nothing to gain by telling you the truth about vent free gas logs. Be smart, you just can't breath the fumes.......Thanks for allowing me to address this issue. I wish I had found your site before my purchase. And to think I was going to invest in another vent free system thinking my first set was not operating properly.

Thank God for the internet and The Chimney Sweep.
Gary Gingrich


#14: Suffering from black lung
Date: Thursday, February 14, 2002

We too had soot damage in our home from vent free gas logs, to the tune of $41,000. In addition I started experiencing shortness of breath. After 3 months of tests I had a lung biopsy which showed that I have "black lung". Both lungs have soot inside and outside. This is something that will not go away. I'm going to the University of Michigan Medical Center today with the hope of finding out what will happen from this point on. I was told that my lungs are worse than those of a coal miner exposed to coal dust for over 20 years. In addition to the lung problems, I have a heart condition developing because of the lack of oxygen going to the heart. I have read many of your comments and encourage everyone to be checked. It's quite apparent that some of the manufacturers appear to hiding something. The logs we purchased have been discontinued and the manufacturer refuses to say why.

If anyone has similar conditions please contact me at
Greg C. Filer


#15: "Shoe Polish" on walls
Date: Wednesday, February 13, 2002

I found your site fascinating.. wish I had seen it before I purchased my gas logs... now... to my question.. my husband and I recently retired to the country. We purchased a lovely double wide home for this purpose. We had ventless gas logs installed into our fireplace and sat back waiting for cold winter days and nights. It has been two winters now and holy smokes I've noticed the walls of our new home are reddish brown and yellowed as if this home were 50 years old and neglected. The entire house will have to be repapered and painted as soon as the spring thaw occures. I cleaned a picture that hangs over the mantel and the rag was totally brown as if shoe polish had been wiped up with it. This must be very unhealthy to our breathing equipment. Now, is there any way I can hold the manufacturer responsible for the damage to my home?
Thank you.

Sweepy Hi Pat,
We're not lawyers, but it might be worth consulting yours.


#16: Sick of soot, smell
Date: Wednesday, February 27, 2002

We have been experiencing soot problems on our ceilings in a huge family room that has a ventfree gas log set up. It is propane based and I am considering replacing it. What do I have to do to replace it? The company that installed the gas lines and tank stated I just needed a hood to push the heat into the room more. I got the hood and it has not helped. Also, my husband hates the smell which goes upstairs even when the unit is on low. Needless to say, we rarely use it and it cost a lot of money to install. By the way, it is in a regular masonry fireplace that has glass doors and a screen. Can you please advise me?
Mary Jacobs

Sweepy Hi Mary,
If you're mostly looking for the aesthetics of the fire, you can replace your vent-free gas logs with a vented set: you'll find the flames are MUCH more realistic in vented log sets. If you'd like to be able to turn off your furnace while you enjoy your fire, consider a direct vent gas insert. In the sealed environment of an insert, the flame display is positively astounding.


#17: Mom belatedly diagnosed with CO poisoning
Date: Monday, July 29, 2002

I was so relieved to find your site so I could send my mother letters that would validate her as to her health problems of the last two years. She has a ventless system in her new home and her health problems began the first winter of use - it was run 6-8 hours a day. She had sinus problems, headaches, lethargy, dizziness, disorientation, hallucinations and eventually breathing problems. In eight months of use she went from 140 pounds to 99 pounds and when tested at 99 pounds she had a lung breathing capacity of 21%. She was sleeping on the couch most of the day. My sister and I felt like she was dying before our eyes. The doctors were stumped and ran test after test including 2 aids tests and a lung cancer screen.

After the fireplace was turned off for the spring/summer season of 2001 she began to feel much better. She still has residual symptoms - shaking, dizziness, breathing problems and confusion. Her lungs have been permanently damaged and her lifespan has been shortened by several years.

The fireplace manufacturer denies responsibility but is going to run the fireplace and do a CO test. It is very hard to prove that the fireplace is responsible for her condition. We are searching specifically for evidence that these systems could have been the cause of her problems. If anyone has any information about ventless symptoms that could help us PLEASE email me at
Stephanie Mosely


#18: Appreciates the info
Date: Friday, September 6, 2002

I applaud your site and information about vent free appliances.
Keep up the good work.
Chad Clack


#19: Thanks for the website
Date: Wednesday, September 25, 2002

I too purchased one of those vent-free gas fireplaces, and experienced the headaches, plants dying, and moisture problems. I also found the house had a mold problem. Your information about the CO issues explain a lot.
Thanks again for the VERY informative website.
Chris Hammerbeck


#20: Gas Company warns against buying vent free
Date: Monday, November 4, 2002

I was very close to buying a vent free fireplace for my home. I just happened to call my gas company to see what the cost would be to install gas lines for this. The man I spoke to mentioned that I may want to think twice about getting a vent free model due to the odor. He said he had a customer who had one installed before talking to him and they are extremely upset about the odor. He told me he just wanted me to be aware of this before spending a lot of money on one. Well, I am thanking him a thousand times over. After he told me this, I decided to do a search on the Internet about odors emitted from vent free fireplaces, which is how I found this web site. After reading these letters, I am so glad that I didn't waste my money! Thank you so much for this information. If I ever buy a gas fireplace, it will be a vented unit only.
Dianne in Ohio


#21: Getting rid of vent free logs
Date: Saturday, December 21, 2002

We are replacing a [vent free] log set. Thought I was alone in my complaints until I read your site. Both the manufacturer and my installer acted like I was the only one who had these odor and health complaints. Even with a CO2 meter which read 0, we still felt sick. On top of that, we had mechanical problems, and even though the working parts of the unit were replaced, still had the same problems.
Thank you for refusing to sell vent free products.
Karen Rossi


#22: Will conversion from LP to natural gas stop "room poisoning"?
Date: Sunday, January 5, 2003
We have a ventless propane fireplace. We've learned it's poisoning the room with black smoke and causing all sorts of problems. Can we convert this ventless to burn natural gas? What are the health problems associated with natural gas, and the difficulty converting propane to natural gas? We might also want to use the same system upstairs if possible.
Please advise.
Thanks, Kevin

Sweepy Hi Kevin,
Converting your vent free fireplace from propane to natural gas won't affect the combustion emissions that are poisoning your room; the emissions from both fuels contain the same poisons. If you want to eliminate the room poisoning, your only option is to replace your vent-free with a vented model.


#23: Second try for vent free, having same problems, looking for support group
Date: Wednesday, January 29, 2003

We bought our first [vent free] in 2001, and it sooted up our house. The serviceman the dealer sent out to inspect it said the [vent free] was faulty. We believed the dealer when he said no safety problems had been reported, and that this was just an isolated incident, so we purchased a replacement. The second [vent free] has a redesigned burner (the company is saying this was done for cosmetic reasons only), and although it is not emitting soot that we can readily see, our home still has damage from soot. After we paid for painting & cleaning at the end of the first season and had the heater cleaned it emitted soot again the following season. My daughter has recently seen her doctor because of severe headaches. We had no idea that the [vent free] could be causing this. I am terrified now.

I have questioned the manufacturer repeatedly about safety, and about the fact that we're living with the soot. The manufacturer and their lawyers are denying that the [vent free] is malfunctioning. Instead, they have said that it wasn't properly installed and that maintenance wasn't done, that the report the dealer sent in said that the [vent free] was clogged with dust and debris.

Is it possible to let the persons who have contacted your web page know that they should contact the U.S. Consumer Product Safety Commission in their area regarding problems they have with their vent free heaters? I have also contacted the Attorney General's Office and will not stop until something is done to stop the danger sold to us. If there is an organized support group please E-mail me at


#24: Removing vent free fireplace because of toxic by-products
Date: Saturday, February 8, 2003

I recently finished my basement and decided to install a ventless fireplace to help heat the basement during the winter months. I was assured from several different store owners that vent free is completely safe, and that they burn so efficient (99.9%) that there is no concern over carbon monoxide (CO) levels, smell, or O2 depletion. My basement is 1200 sq. ft. and open. The fireplace was installed by a licensed workman. Despite turning the gas log set on low and allowing for adequate ventilation, the unit still produced a lot of odor and high levels of CO (over 20 PPM within 1 hour). I called the store where I bought the unit and they said that I should try "curing the logs" by burning it on high for about 6 hours. I explained that this does not account for the high level of CO. He said that up to 30 PPM is considered safe. I did a little research, and it turns out that IAQ guidelines allow a MAXIMUM CO level of 25 PPM/1 hour. In addition, I removed the logs and the burner unit still produced high levels of CO and odor. For the safety of my family and those who may purchase our house in the future, I am removing this fireplace. I believe that anyone considering buying a vent free should use common sense in this decision. Natural or LP Gas fuels produce toxic by-products. Period. The "studies" referenced by many sellers of vent free fireplaces are sponsored by the vent free gas log industry, and the results are inherently biased.
Mark Caswell
Saline, MI


#25: "Horror Stories" help make decision for vented fireplace
Date: Tuesday, August 5, 2003

I went to three fireplace stores today and each salesperson told me that the vent free models were hands down a better choice. I just came across your site as I was looking for vent free fireplaces online. After reading the countless emails of horror stories regarding vent free fireplaces, I have decided to purchase a vented model instead. I am shocked that these vent free models can still be sold with all the health related illnesses they can cause. I'll make sure to sway people away from vent free fireplace models in the future.
My family and I thank you.
Chris and Erin Minchk


#26: Saving lives
Date: Saturday, November 8, 2003

Thank YOU for this outstanding website. People need to know the truth about vent free heating appliances.
You are saving lives.
Donald Dyall


#27: The tobacco companies say these new cigarettes are less poisonous, so let's light up!
Date: Saturday, November 15, 2003

Can you please post an update [on vent-free fireplaces], given recent advances in manufacturing and technology? I understand that models built in the last two years are much better, release next to no CO or other gases, and are much more efficient than older ones, and the information on your site appears somewhat dated.

SweepyHi Rache,
Thanks for the inquiry! We update this page as new letters come in and time allows: we received your letter today, and as you can see, it is already posted above. If you look further, you'll find that well over half of the letters on this page were written within the last two years, and they indicate that the newer "less-poisonous-than-before" vent-frees are still causing sooting, odor, moisture and health problems.

As to the other pages in the vent-free section of our Sweep's Library, there has been no cause to update them. Consumer Reports Magazine has not rescinded its 1998 cautionary statements regarding vent-frees; in fact, they published the same warnings on their website as recently as January, 2008. Air quality scientists like Jim White have not changed their stance regarding the potential hazards of "living in a chimney." Canadian health codes still prohibit installation of vent-frees in that country. The websites of the American Lung Association (ALA), the Center for Disease Control (CDC), the Environmental Protection Agency (EPA) and the Mayo Clinic still caution against the use of vent-free products.

Also unchanged are the ongoing claims by vent-free fireplace manufacturers that their newer models are less poisonous and troublesome than their earlier models. We view these claims with some skepticism, as those same manufacturers have always maintained that their products, even the earlier models, are completely safe and trouble-free, while our observations and the feedback we get from vent-free owners provides much evidence to the contrary.

The bottom line from our perspective is, why should you accept any level of room poisoning from your gas stove or fireplace? The direct-vented gas products we choose to sell consume no oxygen from your breathing space and introduce no carbon monoxide, carbon dioxide, nitrogen dioxide, unpleasant odors, moisture or soot into your house. They cause no headaches, nosebleeds, mold spores, or soot damage. As hearth product retailers who feel we have a responsibility to be concerned about the safety and well-being of our customers, that's the only standard we find acceptable.


#28: Legislation needed
Date: Monday, December 29, 2003

I was doing research on these products and found your site. I too have a vent free that has sooted my entire house before I figured out where all this black dust was coming from. My curtains, my carpet, my clothes, you name it, it's black. I think the time has come to unite together and get legislation passed to eliminate these health hazards. Less than 6 months after my vent free was installed, I developed a thyroid disorder. Can I attribute it directly? No, but I can attribute this sooty black dust to my coughing and feeling ill when I use it. The question here is, how many of you posting at this site agree and would be willing to participate?

I am tired of the service man coming to my house and checking this heater and pronouncing it perfectly safe when I know it's not. I am compiling a notebook of all the health issues associated with these products and documenting case histories. I am not a lawyer, but I know when something is unsafe and needs to be changed. Please have your site visitors let me know if they are interested in trying to get a resolution to this issue. Please contact me via email at


#29: Ready to sue
Date: Saturday, January 17, 2004

I wish I could have found this site before. I too bought a set of nonvented fireplace logs from a dealer that sold [Manufacturer] products. A couple of months later my whole house and contents need cleaning. Black soot is everywhere. The installer came back and double-checked, and said he installed them correctly and that I must have got a bad set. After both he and I contacted [the manufacturer] with no satisfaction he said I might as well get a lawyer. That's what I'm in the process of doing right now. How can this be? How can a company like [Manufacturer] sell me something and after it ruins my house tell me that it is not their fault, that it is the layout of my home or that it was not installed right, when it was installed by one of their licensed dealers? Any suggestions would be really helpful. I am out over $15,000 for cleanup and repainting.

Sweepy Hi Kevin,
All I can do is suggest you contact an attorney.


#30: Vent Free Safety Alliance website on the way
Date: Monday, January 19, 2004

Greetings fellow Consumer Advocate! I am John Galloway of Hearth Services. We are gas heating systems service and maintenance company serving North and South Carolina.

I am a founding partner of the soon to be public Vent-Free Gas Safety Alliance. I have a special request of you as well as an invitation to join our new association.

We are finished with basic structure for our web site. We are now organizing our content, and the site is not open to the public at this time. We admire your position on vent-free heating appliances and would appreciate your permission to publish various letters from your site onto our web site.
John D. Galloway
Hearth Services Fireplace Experts

Sweepy Hi John,

Thanks for the invitation to join your association, but a visit to your website-in-progress reveals that your members will be companies that service and repair vent-free products. Our company's gas service technicians don't work on vent-frees, mostly because they don't want to inherit the barrage of complaints listed in the letters on this page, and also because of potential liability issues (notice how many of the letter-writers are planning lawsuits?).

Here is our mission statement regarding vent-frees:
If you're buying a gas stove or fireplace, buy a vented model, not a vent-free.
If you already have a vent-free stove or fireplace, replace it with a vented model.
If you can't or won't replace your vent free, don't use it.
If you must use your vent-free, open a nearby window ALL THE WAY, limit fires to a maximum of two hours per day, and get MONTHLY tune-ups from a qualified professional.


#31: Many, many thanks for the information
Date: Thursday, February 19, 2004

Thank you for all the info on vent free products. I was planning on buying a 30,000 btu vent free stove that was on an internet website as a close out. All the vented products seem to start out higher, so I got so excited when I found this stove.

I am now not going to buy it. Thank you for your information. I do not want to take a chance with my health. When I called the manufacturer, I asked if there was any additional info that he could provide for me. He said that many customers open a window. I thought that to be strange because then all the heat is going out. After reading your info, I now understand. Thank you thank you thank you. (I may have to save for another year to get heat in my basement, but it will be worth it).
Thank you again,
Freezing But Healthy In California.


#32: Can we vent our vent-free fireplace?
Date: Saturday, February 21, 2004

Wondering how we can vent our ventless fireplace. We are experiencing odor. It's a brand new home and we never realized that they installed a ventless system. We are told that a chimney could not be put in because the pipe on the roof would not be 8 feet from an existing bedroom window. (Which is building code.)
Any suggestions?
Diana Haake

Sweepy Hi Diana,

Thanks for the inquiry! There might be a way to vent your vent-free: consult with your dealer or manufacturer and see if your fireplace is cross-approved for partial or total outside venting. If so, you might be able to vent the exhaust to the outside, unless the only technique available would also violate your thru-the-roof code. If your fireplace isn't cross-approved and the fireplace is located on an outside wall, you could replace it with a direct vent fireplace: these vent out the backwall instead of through the roof, as shown in diagrams #1 and #2 on our
direct vent info page.


#33: Can we vent our vent-free fireplace?
Date: Tuesday, March 9, 2004

Hope you can help us. Have a beautiful Amish-made ventless fireplace. Can not use it. Everything yellow. This year we could smell gas, so we haven't used it at all. Too afraid. Is there a way to convert it to be vented outside?
Thank you.

Sweepy Hi Herkywings,

Thanks for the inquiry! As you can see in our answer to the letter immediately above, there might be a way: consult with your dealer or manufacturer and see if your fireplace is cross-approved for partial or total outside venting: if so, you might be able to vent the exhaust to the outside. Prepare to sacrifice heat, as once you vent a vent-free, it can no longer deliver the heat into the house with the exhaust gases, the way it was designed to do. A better choice would be to replace your vent-free with a direct vent model, as these are designed to maximize heat transfer into the room while at the same time venting their exhaust outside.


#34: Other airborne poisons
Date: Tuesday, April 13, 2004

We bought a house with a vent-free gas fireplace already installed, and felt pretty safe with it because we studied the owner's manual and were always careful to open a nearby window and limit the duration of our fires. However, we soon encountered a problem that doesn't appear on your website (that we can find).

We painted our living room, and when we lit the fireplace soon after, the whole house was filled with the most awful smell that made us both sick. We called the manufacturer, and were told you can't paint, because anything airborne in the house (like paint fumes) gets drawn into the fireplace flames, where it burns and creates its own nasty emissions! They told us this also applies to the fumes that come off new carpet, room deodorizers, hair spray, household dust, pet hair, spray cleaners, candles, etc. etc. etc. Pretty much anything in the air gets sucked into the flames and stinks up the house.

Since then, whenever we have a fire we're almost afraid to move, lest we stir up some dust or something that will hit the flames and raise a stench. The dog is banished to another room, so he doesn't scratch himself in front of the fire (burnt pet hair is the most sickening smell you can imagine).

You're obviously up on the chemicals contained in the gas exhaust, but do you know what emissions you get when you burn the vapor from spray cleaners or any of the other stuff that floats around the air in a typical house?
Ray & Eileen

Sweepy Hi Ray & Eileen,

Sorry, we're not aware of any studies that have been done about health problems deriving from breathing the emissions from burned vapors, fumes or pet dander. However, we're sure your description of the bad smell these things generate will help dissuade some people who are considering vent frees, and thank you for sharing your experience.


#35: Poisoned over time
Date: Thursday, June 3, 2004

When we were told by many people that vent free units were dangerous and malfunctioned, we would always come back with that fact that our family had a unit that was excellent. Compared to electric heat, we saved a ton of money and had a WARM house.

However, we had no idea that we were being slowly poisoned by carbon monoxide. I always react extremely to kerosene and wood stoves, but this unit never seemed to bother me much when we got it, so I assumed that it was okay. BIG MISTAKE.

After becoming violently ill at a restaurant a few weeks ago, we determined it was the flu. It took only a week before I collapsed and my three year old laid on the ground lethargic- FINALLY it dawned on me that it was our heater.

Carbon monoxide detector showed reasonable low levels (under 50 ppm) but the damage done by this unit to my body in particular and to that of my family can not have a price on it.

After only a week without any heat, I am still suffering greatly from the poison. I wish that we had gotten rid of our heater when we were warned a few years ago, but we did not.

PLEASE, if you are thinking of having a unit like this, or any other vent free unit, PLEASE LISTEN TO THE WARNINGS. The CO levels will accumulate in your body and it might be too late before you discover how much damage it is doing to you. Believe me. Carbon monoxide (CO) poisoning is something you do NOT want to experience. I know from personal experience.
Feel free to email me at any time about this. I would be glad to talk to you about it.

Posted at


#36: Telephone Inquiry: Why should a healthy, non-pregnant young adult be concerned?
Date: Thursday, June 10, 2004

Q: In your answer to Rache [see letter #27 above] you mention that the websites of the American Lung Association, the Center for Disease Control, the Emissions Protection Agency and the Mayo Clinic all warn against the use of vent-free products on their websites. I had a look, and it seems to me that most of these cautions are directed primarily at young children, small animals, pregnant women, the elderly and people with diabetes, asthma or cardiovascular problems. I don't belong to any of those groups, so I don't think those warnings need concern me.

I've been looking at two identical gas stoves made by the same company: one is direct-vented and one is vent-free. To me, the only difference is the vent-free is $150.00 cheaper, and doesn't require a $200.00 vent kit! A net savings of $350.00 is a powerful incentive. I see no reason why a healthy young adult like myself shouldn't go vent-free.
What do you think?
A Long-Distance Runner in Vermont

Sweepy Hi Marathon Man,

We think there's a flaw in your reasoning. Just because certain groups are at greater risk from exposure to gas exhaust, it doesn't mean that others are at no risk whatsoever. Example: when the AMA warns seniors to be extra careful walking on icy streets because they're at greater risk of breaking a hip should they slip and fall, that doesn't mean you won't break your hip should you hit the same patch of ice.

Even allowing your unsupported contention that a healthy young adult with runner's lungs isn't as likely to experience severe health problems from sharing his breathing space with the poisons contained in gas exhaust, you might want to take the following Vent-Free Purchaser Quiz:

1) Do you think exposure to gas exhaust will have no adverse affect on you at all? Isn't it logical to assume that if the very young, aged and health-impaired are at serious risk from exhaust gas inhalation, even a healthy set of lungs might be adversely affected?

2) What about the other problems vent-free fireplaces can cause? Wouldn't you pay $350.00 to eliminate any chance of the unpleasant odors, blackened walls, moisture damage, mold and mildew vent-free owners complain about?

3) Vermont Winters are mighty cold. Are you sure you'll be willing to open a window, as vent-free manufacturers say you must, every time you have a fire? And are you sure you'll be willing to limit your fires to the mandated couple of hours a day?

4) What about the other folks who occasionally share your home? Wouldn't it be nice to be able to have a cheery fire when Granny visits, or your friends with infant children? How about your buddies who come over every week for poker night who have never mentioned they have diabetes or asthma?

Scoring: Buy the vent-free if your answer to all the above questions is "I don't care."


#37: Sooting, chronic lung condition
Date: Thursday, September 30, 2004

We have a 4000+ square foot home that now has soot all over it. Our insurance company states this happened over time so will not cover it and have attributed this problem, after calling in several experts, to our unvented gas fireplace. We are now faced with the task and expense of cleaning and repainting our entire house. We have 18 foot ceilings in places and this will be no easy task. Additionally, I quit my job in 2001 due to respiratory complaints and started a different job. I thought I had environmental allergies at the workplace but now find the culprit is in my own home. I have been told that I have bronchiectasis, a chronic lung condition caused by irritants. They assumed it was due to measles and pneumonia I suffered as a young child, however, now I am questioning whether it was the fireplace. We only used it rarely and for no more than 2-4 hours, maybe 15 times per season. The house was built in 1997 and the fireplace is installed in a large open room with an open floor plan that far exceeds the cubic foot requirement. Our beautiful house, in which we took so much pride, is now a sooty dingy mess. I am ashamed to have anyone in our home and now am experiencing chronic lung problems. Is anyone having any success in collecting damages from the manufacturer?
Thanks for your prompt response.
Carole Foster

Sweepy Hi Carole,

Thanks for sharing your experience. Several of the others whose letters appear on this page mention lawsuits, but none have written back to share the results. If any of you are revisiting this page, will you please click our E-mail link at the bottom of this page and fill us in on the outcomes of your lawsuits (and CC a copy to Carole)?


#38: Sooting, who do I contact?
Date: Thursday, September 30, 2004

I have been reading all of the emails on your web site concerning the black soot that the unvented stove gives off. I have had a problem with my stove for 3 years and I always thought it was from something I did wrong while installing. I have changed the connections numerous times with no change. Who can I contact to check my stove? Also, for safety reasons should I go to a different type of stove?
Tom moon
Damascus, MD

Sweepy Hi Tom,

If you've read the letters above, it should be obvious that your healthiest and least-sooty solution will be to chuck your vent-free stove and replace it with a vented model. If you choose to keep your vent-free and want to try to tackle the sooting problem, your first step should be to contact the manufacturer and see if there's an authorized service technician in your area. Observe how he tunes up your stove carefully, as most manufacturers require that vent-frees be serviced at least once per month during the heating season, and you'll want to save the expense of bringing in a pro in the future.


#39: Retired Hearth Products dealer refused to sell vent-frees
Date: Wednesday, October 13, 2004

Thanks for having the courage to address the serious issues of vent free products and refusing to make a quick buck on it. I was part owner of a chimney sweeping/stove sales business for 10 years and we also refused to sell anything ventless. It never made any sense to me that if anyone would actually research it and read the owners manual, why they would still decide on buying one. (stubborness, most likely. they always think they know more than the professionals) If it is dangerous for most types of people, it's dangerous for them too. But I know that you have heard from many a customer, like we did, who said something like "it hasn't killed me yet" regarding their dangerous situations. We quit our business partly for that reason. We had a good company and were consciencious about the work we did. We did not sell anything that we wouldn't use in our own homes, and we tested out many different stoves in our home. But, we would NOT sell anything ventless and always warned our customers about it if we heard them talking about possibly buying them.

Not many businesses will forego profit for the sake of protecting the people because many dealers & manufacturers do not have a conscience. It's all about what sells and lines their pockets.
Xanndra Boehler


#40: Can we make our vent-free gas logs safer?
Date: Wednesday, October 13, 2004

We purchased a propane vent free gas log set for our house last weekend. I just discovered your website today. I should have seen it BEFORE I bought the logs! We have a central heating system that is new and works well. We burn wood in our basement fireplace in the winter for supplemental heat because the basement gets cold. The upper main floor is where we have installed our vent free logs. We wanted them for ambiance and for occassional supplemental heat. Sometimes that room gets chilly when the fire is going in the basement because the furnace doesn't kick on as much. The basement gets very warm and the main floor cools down. I thought we could use the vent-free gas logs to balance out the heat a little. Now I am worried that we bought the wrong thing.

We installed the vent free system in an existing vented fireplace. Do you think the health concerns, soot concerns, etc are minimized if we open the flue an inch? I tried it and we are still getting heat from the system with the flue open a crack. I don't want to use this vent free if we are going to be sick from it, but if opening the damper would minimize the health risk, I would keep it.
Your opinion is appreciated!
Nicole Gallagher

SweepyHi Nicole,

By all means, open your damper enough to vent as much of the poisonous exhaust as possible. Had you bought a vented set, it would have come with a clip to hold the damper open about an inch, so yours sounds like a reasonable plan.


#41: Vent-frees compared to cigarettes and asbestos
Date: Friday, November 12, 2004

I am a fireplace dealer in Ohio. Over and over people come in with the thought of placing a ventfree appliance in their home. Over and over I explain the problems associated with the vent free units. I lose many sales because other companies tell the client that vent free fireplaces are no more dangerous than a gas range (except that you don't have a big exhaust fan over it). I would rather lose the sale now than have suffering, unhappy customers forever. I want my customer to be as happy with their purchase 5 years from now as they are the day they bought it and, unfortunately, that will not happen if they purchase a vent free. If that makes me a bad businessperson, so be it.

We, as an industry, need to educate the consumer as to the best possible products for their needs. A direct vent or electric fireplace will give them all they need and want without compromising their health or the health of the family. Please keep up the good work with educating the consumer. I will recommend your website to anyone contemplating ventfree and will continue to fight the good fight here in Ohio. Just remember, there was a time when people thought cigerette smoking and asbestos were good for you too!
Thank you,
Donerae Testa
The Place
North Royalton Ohio


#42: Gas Service Technician wouldn't even consider a vent-free fireplace
Date: Tuesday, November 30, 2004

Hi, I have been a HVAC service tech for almost 30 years and when I was going to purchase my fireplace, vent free did not even enter my mind. I knew of the potential hazards but I did not realize the extent until I stumbled upon your website. Why contractors actually sell this stuff amazes me. Have our morals dipped this low, to knowingly endanger lives for a buck? They know the potential dangers when they sell [vent frees] but still continue. They won't stop until they are forced to stop. You are carrying the torch in the battle against vent frees.
Keep up the good work!
Bob Kirr

SweepyHi Bob,

Thanks for the support! Please note that we don't carry the torch into people's houses.


#43: Decided to go with direct vent stove
Date: Wednesday, December 1, 2004

I was about ready to purchase a vent-free gas stove, but still felt a little uncomfortable with the concept. It was hard to buy off on the fact that the system burns so efficiently that there is no substantial exhaust. After reading the horror stories on your web site, my wife and I have decided to go with the direct vent stove. Thank goodness I was able to stumble onto your web site.
Thanks so much for making it available.
Michael R. Sylvain, P.E., R.L.S.
Phoenix, AZ


#44: HVAC dealer warns cunsumers against vent-frees
Date: Monday, December 20, 2004

My husband and I own a heating and cooling business and occasionally we are asked about vent free fireplaces. I always tell everyone to avoid vent free because of the many problems associated with these vent free units including condensation on windows and noxious gases venting directly into the home. If homeowners have small children, health problems (asthma etc.), pets (vent free will kill birds fast), they will regret ever installing a vent free fireplace. From the letters I read on your website the health risks are not limited to people with health problems.

Also, I wonder if people read the instructions that are included with the vent free fireplaces. The one I read clearly states that windows must be cracked open and units have a maximum operating time.

If homeowners want to enjoy a fireplace, the only way to go is with a VENTED unit. Homeowners, do not try to save money by purchasing vent free fireplaces!

I will direct all further inquiries about vent free fireplaces to your website. Hopefully these vent free units will be recalled and outlawed in all 50 states in the near future.
Beth Koesterer


#45: Vent-free Owner: much maintenance, vigilance required
Date: Tuesday, December 28, 2004

Vent-free doesn’t mean maintenance free. Operation of a vent-free gas fire place requires regular cleaning and dusting of the unit and its surroundings to keep the CO levels down. Average CO levels of both CO monitors in my home are around 5-10 ppm max. year round. Peaks are more notable after getting out of a car after a few hours in traffic, as clothing will hold in a number of different compounds including CO. When peaks are noted above 10 ppm, during the winter season when the fireplace is in use, a good cleaning and dusting of the unit brings the levels back to 5-10 ppm.

Any smell of natural gas will indicate a problem with the unit not igniting completely. A single blocked hole in the manifold can create a delay in the firing of the rest of the unit leading to the smell of natural gas; you should turn off the unit and have it inspected for a possible blockage. The smell of kerosene when the unit is burning has also been noted when the gas company installs or upgrades a gas main in the area. This is a rare occurrence in some areas, but for newer developments it might not be as rare, as the welding of the new line and the cleaning process to remove the slag sometimes leaves a residue in the line.

Yes, I have to wash the windows in my home on a monthly basis, but the problem is not as bad as a neighbor who burns a lot of candle in her home. I do have to run a dehumidifier on occasion in the winter but I’ve always had to do that to keep the moisture levels down in an older home that doesn’t have an automatic venting system now required.

Also how many people have their CO monitors calibrated on an annual basis or replace the CO unit annually (much cheaper)? Read and understand the entire instructions with any CO monitoring system before you set it and forget it. People who trust their lives to their CO monitors, at home or place of business have the units calibrated regularly and test their units before each use. How many people fill a bath tub with hot water and just hop right in without testing the temperature?

Every source of heat requires some amount of maintenance, some just require a little more. Maintenance wise I would place a vent-free fireplace halfway between a wood fireplace and electric base board heat. Cost wise vent-free is the lowest price per BTU, but what are the other costs in your time and health?
Ed Scholfield

SweepyHi Ed,

Thanks for the comments! You seem extremely well educated as to the maintenance and operation of your vent-free fireplace, and we agree with most of your points, but would take exception to your statement that "vent free is the lowest cost per BTU". We have long maintained that, when you factor in the hidden expenses associated with vent-free usage you mention, such as the monthly cleaning and servicing of the logs and burners, monthly window cleaning, annual CO detector calibration or replacement, operation and maintenance of a dehumidifyer, etc., and then consider that vent-frees can only be used 2-3 hours per day, the advertised maximum annual heating savings of 3% to 7% over a direct vented gas heater totally disappear.

What doesn't disappear is the long-term exposure to low level CO gases and other gaseous emissions associated with vent-free use, and the harmful health affects that result. Despite your unusually diligent best efforts to keep your vent-free fireplace tuned to minimize harmful emissions, you report that the CO level in your home fluctuates between 5ppm and 10ppm,, a level that an increasing number of medical professionals consider unacceptable. If you haven't done so yet, please click here to read about the study entitled "THE EFFECTS OF CHRONIC EXPOSURE TO CO", sponsored by the British non-profit organization CO Support (you'll also find a link to the text of the entire report on the same page).


#46: Soot, Soot, Soot
Date: Wednesday, January 5, 2005

We purchased a vent free gas log unit 3 + years ago, and now have soot, soot, soot everywhere. Ceilings, walls, inside cabinets, refrigerator, and on everything plastic we own. Western Natural Gas installed the units and has been the only company to service them. We noticed the soot back in March, they came and picked up the logs, "fixed" them saying they would take care of the soot damage, today we learn that their insurance company denied our claim. Has anyone had luck going after the manufacturer "Vanguard"?
Kelly and Doug Stephens
Jacksonville, FL


#47: Your website saved me today
Date: Monday, January 10, 2005

In my search for pros and cons for vented vs vent-free, I came across your site. Enticed by the promise of increased heat distribution, I was leaning towards a vent-free gas log set. After reading the letters on this site, I can honestly say your website saved my life today.
Thanks and have a great day!
Melissa in Dallas


#48: Any way to vent these fireplaces?
Date: Monday, January 10, 2005

Hi - I've been reading your site concerning the dangers of vent-free fireplaces and accounts by those who have suffered health issues due to their ventless fireplaces. I was hoping you might be able to offer some advice. My parents are just about finished building their home and I recently learned the fireplaces they have installed are all ventless. I was actually trying to find a smaller, bedroom model that my Mom was interested in for their bedroom and it was during this search that I ran across a lot of disturbing opinions on the use of vent-free fireplaces.

I've warned my parents about the dangers I've read about vent-free fireplaces, but I know they don't have the money to just replace their fireplaces with vented models. So, I was hoping you might offer some advice on whether it is possible to run venting to their existing fireplaces? One is located on an exterior wall, so I was thinking that a direct vent might be an option? The other fireplace is a 2-way that is not located on an exterior wall, but I thought that perhaps venting could be run from the fireplace down through the floor and then out to an exterior wall along the basement ceiling? Or maybe the 2-sided fireplace might vented up through the attic and roof. Do you have any thoughts on this? Can most/all models be converted, or is this not really a feasible option?

I appreciate any thoughts, advice, or additional resources that you might be able to offer to help. All of the research that I've seen discussing the dangers of these fireplaces has me very concerned. Especially as my Mother has a slight asthmatic condition.
Thank you for your time.

SweepyHi Rianna,

As mentioned in response to previous letters above, some, but not all, vent-frees can be vented. To find out if your parents' fireplaces can be vented, contact the manufacturer. You won't be able to vent the see-through downward, so you'll need to investigate a vertical location for that pipe. Note: even the people who sell vent-frees caution against use by asthmatics, so if the fireplaces can't be vented, you need to convince your folks to replace them with vented models.


#49: Vent-free owner saw doctors more than family & friends
Date: Friday, January 14, 2005


I am so grateful to find your website. I had a vent-free fireplace installed in August, 2003, which never functioned properly. Over a period of 15 months, every part was replaced at least once. Eventually, a new burner was installed for the same model in 9/04. It too did not function (front row would light - not back row). Another model was installed in 11/05. This one would not light if the gas furnace was on!!

In the interim, I was constantly ill - eye, throat, blood pressure and heart problems - and was hospitalized four times. I had a pacemaker put in, felt fine in the hospital but once I came home, felt awful. I saw doctors more than I saw family or friends. I was practically an invalid. Eventually I called my local gas and electric company and who discovered I had a gas leak where the gas pipe joins the burner. It was leaking badly.

Here is my question: I want to sue these disgracefully incompetent people who assured me repeatedly that the installation was fine. But, I need expert medical advise as to the short and long-term effects of natural gas and carbon monoxide. My doctors tell me they have never had a patient who was exposed to natural gas, etc. Are you aware of anyone who has successfully won a lawsuit regarding a vent-free fireplace and what type of expert is needed. Toxicologist, industrial or environmental specialists? Or, can my doctors find out this type of information.

In the meantime, I am being treated by a pulmonary specialist for continued breathing problems.

Any help you can give me would be so appreciated. My advice to anyone is never, never get a vent-free fireplace. There is a reason why there are vents in the fireplace, I guess.

Thank you.

Sweepy Sorry about your medical problems, and thankful that you chose to share. Nobody has written to us with the results of their lawsuits, but there's a non-profit organization in England dedicated to fighting CO poisoning that may be able to help you with specialists, documentaion, etc. They are called CO Support, and you can read about them online by clicking here. There is a contact link at the bottom of the page.


#50: MD switches out vent-free in new condo
Date: Monday, January 31, 2005

Enjoy your website. We just moved into our new condo where all units but ours have a ventless fireplace unit. I changed out to an electric unit. This was a last minute change-out and there was no time for installing a vented fireplace. I'm concerned for my fellow owners. This same builder used ventless units in his previous condo project, also in Tacoma. The construction is tight, and in my opinion, these fireplaces should not be used more than the 2-3 hours recommended. What is the Washington State law regarding these units? Has anyone ever forced a builder to replace the fireplaces?
Terrel J Michel, MD

Sweepy Hi Doctor,

Thanks for the inquiry! Washington State has yet to pass any legislation regarding vent-frees, we're sorry to report. A few people have written to say they've "forced" their builders to switch to vented fireplaces during construction, but our impression was their hammer was more a matter of economics than of law (put in a vented fireplace or I won't pay you).

To our knowledge, there is no organized anti-vent-free lobbying effort at this writing, so our legislators probably see this issue as a wheel that isn't particularly squeeky. Since you obviously have strong feelings about this matter, we urge you to write your legislators and let them know. If enough concerned people make the effort, legislation similar to Canada's banning vent-free fireplaces might be forthcoming.


#51: Vent-free dealer glosses over problems, loses customer
Date: Tuesday, February 15, 2005

I just wanted to say thanks to all of you who run this web site. I was considering a vent-free purchase to install in my basement, but after reading all these horror stories it won't be happening. My wife has asthma and my allergies are hard enough to deal with without that problem. I would also like to add that I was at a home show in Cobb County, GA and two of the dealers told me of the problems with vent-frees and directed me towards the direct vents. When they first told me of the problems I didn't believe them because the dealer I'd been planning to buy the vent-free from never, ever mentioned the health concerns or the moisture problems. Needless to say, I won't be buying from them. Again I would like to say thank you to everyone for their stories and information. Question: are there any problems with the direct vent fireplaces?
Dennis Ponte

Sweepy Hi Dennis,

Not a single one of the problems described in the letters above apply to direct vent products. Direct vents don't dump gas exhaust into your indoor breathing space, and they don't consume any of your oxygen: they get their combustion air from outside, and vent their exhaust outside.


#52: Was sold on vent-free, now going vented
Date: Tuesday, February 15, 2005

I just finished my basement, and was going to use a ventless propane fireplace for heating. My gut feeling didn't like the ventless idea at all, but after a lot of shopping, and talking to so-called professionals I was sold on it. I figured I would do one more search on ventless vs vented fireplaces before purchasing, and I found your site. I can't thank you guys enough. You just saved my family from a lot of potential problems. I will definitely get a vented setup installed by a professional.
Thanks again!
Don Hinckle


#53: Furnace Tech finds vent-frees, not oil furnace, causing sooting
Date: Tuesday, March 8, 2005

I'm glad I found your site. I was at a customer's house yesterday. She wanted me to check her almost new oil furnace, (installed by the company I work for), because her house was sooted up with all of the telltale problems others have reported on your site. Investigating further I found that she had an unvented fireplace log set upstairs and an unvented stove-type fireplace in the rec room. As I told her, "The Indians knew enough to put a hole in the top of the teepee." I am calling her immediately with your website address.
Fred Jordan
Oil Burner Technician


#54: Has had no problems with vent-free, but cautions against nuclear radical production
Date: Monday, July 11, 2005

Hey there,

I have very mixed emotion about the entries at the website. 8 years ago I built a house and installed a 48,000 Btu vent free fireplace. We did the burn off time and NEVER had a CO reading above 3ppm. The house was built very tight. In fact so tight that your ears would pop when the front door would shut. We installed 2 CO detectors and had both the fire department and the local gas company come check the fireplace (they both found that the cook stove/oven produced more CO). We enjoyed the fireplace and the tremendous savings in the fuel bills. I am thinking that these units your web posters have commented on may be susceptible to poor installation, poor quality, or poor understanding of maintenance. In any case I have recently taken a new position with a university in another state and plan to install two vent free fireplaces, neither of which will be used for other than occasional heating on cold days.

Of interest and value to readers of your website would be a few studies that have been conducted that relate vent free fireplace use in basements and Radon gas. There is a potential for the added moisture from the fireplace and the combustion of radon resulting in nuclear radicals to be released (hence the concerns for asthmatics- or anyone worried about lung cancer). Fireplace (vented or vent free) installations in basements should be done in conjunction with a radon test.

Lastly, there are many folks that have had wonderful experiences with ventfree. I would like to see a few of these posted to assure that there is not a bias being taken.

Thanks for your time and best of luck in your endeavors

Michael B. Knight PhD
Assistant Professor Computer Information Systems
John A. Walker College of Business
Appalachian State University

Sweepy Hi Michael,

We publish nearly every letter about vent-frees we get, and for whatever reason, yours is among only a handful we've received defending vent-free products (see #27 above to read the first one, and click the link at the bottom of this page labeled To read letters in defense of vent-free products, click here for the rest).

Thank you for the info on the interaction of vent-frees with radon gas: we hadn't known this combo would produce anything as scary as nuclear radicals. However, we must take exception to your statement that all basement fireplace installations should require a radon test: direct vent fireplaces don't produce any moisture in the room or burn any room air, so even in the presence of radon, no nuclear radicals would be created.

We'd also like to examine the "tremendous savings in the fuel bills" you mention. We'll agree that gas fireplaces, both vent-free and direct vented, can be much more efficient heaters than forced air furnaces, because they deliver the heat directly into the living space without the need for energy-wasting ducting (typically, it would take an 80,000 btu gas furnace to heat the same house you heated with your 48,000 btu vent-free). What we don't agree with is your statement that the fuel savings with vent-frees are tremendous, especially when compared to direct vents.

Let's take a look at the numbers. To create the maximum possible savings you might experience, we'll consider the coldest days of Winter, when your 80,000 btu furnace needs to run continuously to heat your house. In those conditions, that furnace would consume 240,000 btu's every three hours. If you burned your 48,000 btu vent-free instead of the furnace for three hours (the maximum daily usage recommended by vent-free manufacturers), you'd consume just 144,000 btu's, for a net savings of 96,000 btu's, or 40%. This sounds impressive, but it only holds true for the three hours you're allowed to use your vent-free. Since you'd have to use the furnace for the other 21 hours that day, at the end of the day, you'd have burned 1.824 mbtu instead of 1.920 mbtu, for a net fuel savings of just 2%.

Today's direct vent fireplaces achieve delivered efficiency ratings exceeding 86%, which falls a bit short of vent free manufacturers' advertised 99% efficiency, but is still far better than the delivered efficiency of a forced air furnace. If you burned a direct vent fireplace instead of your furnace for three hours every day, you'd save 35% for those three hours instead of the 40% you'd save with your vent-free, which would seem to give the vent-free a 5% fuel savings advantage over the direct vent........ BUT: that advantage, which is pretty small to begin with, only holds true for the three hours you're allowed to use your vent-free! Since you can use a direct vent fireplace all day long with no health concerns whatsoever, your monthly savings with a direct vent fireplace would be 35%, compared to the vent-free's monthly savings of 2%.


#55: Author of letter #54 admits direct vent fireplaces are best choice: more about the vent-free / radon issue
Date: Tuesday, July 12, 2005

Thanks for the reply Tom,
The savings that I was talking about was in comparison to our old furnace. I think that the vented fireplace is the best if it is drawing combustion air from outside and then venting outside. The radon issue is one that comes from pressure differences caused by using indoor air for combustion and then venting it outside. Overall pressure differences cause radon to be pulled into a house and further complicate the situation. Needless to say, a proper working fireplace used the correct way and maintained correctly is best
Assistant Professor Computer Information Systems
John A. Walker College of Business
Appalachian State University


#56: Walls gray, but not because of paint choice
Date: Wednesday, August 10, 2005

I just bought a house with a Superior (SFC) vent-free fireplace (model VF6-CMP). We didn't notice it was vent free until we moved in, and neither did the inspector (the gray wall colors weren't paint - if you know what I mean). Anyhow, it's got to go. Can it be vented? If not, what would nicely fit in its place?
Barry Cushman

Sweepy Hi Barry,

Thanks for the inquiry! Bad news: According to the manufacturer's website, your Superior can't be vented to the outside. Good news: we know of several direct vent models that would fit inside the framing for your VF6-CMP. Choose one that is smaller in every dimension, so all you'll need to do is open up the front of your enclosure, remove the VF6-CMP, take some 2x4's and shrink the existing framing opening a bit, install the direct vent fireplace and venting, then refinish the front. There are direct vent fireplaces that can vent straight back, up-and-out the rear or side wall, or straight up, so you've got every possible venting option going for you.


#57: Thanks to all who have written to share their vent-free experiences
Date: Monday, November 21, 2005

Thank you so much for the online information site. I have a direct venting system that goes out to my back porch. I am having a sunroom built on this back porch and wanted the vent put inside running out through the roof so that no one would get burned by the hot metal. The construction company added this to our contract not knowing how much it would cost them to hire an outside contractor to do this work. Well, they had it assessed and asked me if I wanted to go ventless. I was totally naive about what ventless consisted of so I researched it and came upon your site. Thank you everyone for all your input. I immediately called the construction company and told them that I did not want a ventless fireplace and proceeded to tell them of your website of all the hazards involved in having one.

Your website has probably saved many lives from the potential dangers of ventless fireplaces.


#58: Replacing vent-free due to smell, dizziness issues
Date: Wednesday, December 7, 2005

Q: Can a vent free fireplace be converted to a rear vented unit? My unit is inserted in a small bump out on the exterior wall of the house. All of my neighbors love their fireplaces. They have rear vented units and don’t have the smell or dizziness issues we experience. Temco said no; we should buy another model from them.
Any thoughts?

Sweepy Hi Tim,

Only some vent-frees are cross listed for external venting. If your manufacturer says you need to replace the model you have in order to vent to the outside, thats what you need to do. By the way, if you're going to replace your vent-free, don't choose a cross-listed "ventable" vent-free to replace it unless you don't use the fireplace for heat: once you vent a vent-free, you lose virtually all the heat. A direct vent model, which is designed to maximize heat output into the room while venting the exhaust outside, would be a better choice.


#58: Adding "Glowing Embers" to a vent-free fireplace
Date: Friday, December 9, 2005

Q: Do you sell add-on glowing embers for a ventless gas fireplace?
Thank you,
David Felder

Sweepy Hi David,

Trust me, if your vent-free fireplace didn't come with glowing embers, you don't want to add them. What makes glowing embers glow is contact with the flames, so the embers must be placed in close proximity to the burner openings. If the embers are too close to the burner openings, however, a phenomenon known as flame impingement occurs, and flame impingement causes sooting. In a vented system, sooting is only a small problem: if soot deposits are noted on the fireplace walls, logs, front glass or exhaust flue, it is easy to fire down and adjust the embers so there's no impingement. In a vent-free fireplace, flame impingement will cause soot to deposit all over your floors, walls and furniture.

The vent-free fireplaces we've seen that incorporate glowing embers are specially designed with racks or trays that hold the ember chunks away from the burners. If yours is one of these, and you're looking for replacement embers, consult with the manufacturer to obtain the right type of embers and detailed installation instructions.


#59: No vent-free under this tree
Date: Saturday, December 17, 2005

I was all ready to buy vent free gas logs for my daughter's family for Christmas but wanted to check them out on the internet. After finding your site and reading the letters from owners of these vent free gas logs I think it's best to find out how we can make her vented fireplace less drafty or just close it up. She has a newer home in Delaware and other people in her development are just closing them up. I'm not sure about the codes in Del but none of their vented gas fireplaces have dampers so when they are off the wind comes howling through. I don't want to put my grandchildren in harm's way so until I find more positive independent findings on these vent free logs they are off Santa's list.
Bill Robins

Sweepy Hi Bill,

It might be a little late for Christmas, but here's a gift idea: find the name of the fireplace manufacturer (it is usually on a metal label just inside the fireplace opening at the top of the right sidewall), and contact them to see if they offer glass doors.


#60: Dissatisfied with vent free
Date: Tuesday, December 20, 2005

As with all your other posters, we have a ventless system and hate it. We have been dissatisfied since we installed it in 1999 during a new construction. Do you know if there is any record of insurance companies paying for replacement due to the fumes, health and/or soot concerns?

We are looking to replace ours with a vented system. Any suggestions would be greatly appreciated
Rhonda Trautman
Glasgow, Ky

Sweepy Hi Rhonda,

Sorry, we don't know of any insurance company payouts due to vent-free health or property damage, or even where we might go to look that sort of thing up. Maybe we can help with choosing a vented replacement, though. You can read about our favorite gas direct vent fireplaces on our fireplace main page.


#61: Not told about health cautions
Date: Wednesday, January 4, 2006

You are rendering a terrific service by providing the bulletin board on vent-free gas fireplaces. My wife and I are about to install propane heat in our home. Neither the potential contractor, nor all but a few of the potential dealers, provided any note of health caution regarding vent-free heaters or fireplaces. While one dealer advised us that the exhaust can cause condensation, deposits on window and possibly mold, the CO danger and possible long-term health effects were played down or not mentioned, maybe because the sales staff worried that generating such health concerns might discourage us from buying the vent-free units from them, or even from going with gas as a heating source. They were wrong, because we are going to move ahead and install propane heat, but with vented fireplace and heaters.

We plan to use the printout from your website to further educate our architect and installing contractor. Most important, this valuable information educated us in time.

Thank you,
Shimon Schwarzschild


#62: Can't get windows clean
Date: Friday, January 13, 2006

Q: Our vent free fireplace leaves a film on the windows that is very hard to clean. Cleaned 3 times and film still there. Any suggestions on what will remove this film?
Thank you,
Tanna Carrico

Sweepy Hi Tanna,
Whenever you burn your vent-free fireplace, water vapor and nitrogen dioxide enter the room's airspace. The water condenses on the inside surfaces of windows, where it mixes with the nitrogen dioxide to form nitric acid, which leeches ions from within the glass surface. Once this leeching action has occurred, it is important to remove the acid leechate mixture from the glass, or permanent fogging can result.

To remove the nitric acid leechate mixture from your windows, use a good scrub brush and a mixture of ammonia and trisodium phosphate, then rinse with clear water. This must be done on a regular basis whenever the vent-free is in use, to prevent etching. If the surface of the windows has become fogged, try polishing it with
gas stove glass cleaner, available at hearth product shops, home improvement centers and hardware stores. Gas stove glass cleaner is a mild abrasive paste that looks and works like metal polish: you apply it to a rag, polish the glass surface until the fogging is removed, then rinse with clear water.


#63: Do vent-free "heaters" pose the same risks as log systems?
Date: Monday, January 23, 2006

We are remodeling the attic of a house into two bedrooms and are researching residential vent free heaters, not fireplace log systems. Do they pose the same risks as are detailed on your website?
Thank you,
Dave Nelson

Sweepy Hi Dave,
It doesn't matter if a vent-free gas burner is a stove, a set of gas logs, or a fireplace. If it is vent-free, it is venting its poisonous exhaust into your breathing space. For this reason, vent-frees are a particularly bad choice for bedroom installations. The reasoning is, you might go to sleep one night and not wake up.


#64: Thanks for honest help on vent-free, I was sick for 3 years!
Date: Friday, February 17, 2006

Thanks for the info on vent free health issues! I used [a vent-free] for the last three years. I have been sick, all of the exact health issues as posted by others on your Great site. After reading a couple of comments, I turned the [vent free] off !!!!! Bless You ALL!
Peace ,
Paul Aron


#65: Wasn't told about any usage limits
Date: Thursday, February 23, 2006

Hi. Great website. I saw on one of your responses that ventless units should only be run 2-3 hours a day. I was not told this when mine was purchased or installed. Does this apply to all units? (mine is LP). My current CO detector only reads at 30ppm+. If I get one that is more sensitive and the levels stay below 10ppm, can I run it longer than 2-3 hours per day? This unit is the only heat source in one room.
Thanks for any info!
Victoria Vosburgh

Sweepy Hi Victoria,

The final authority about usage limits for your vent-free will be the manufacturer. Try going to their website and downloading the owner's manual for your particular model. In the fine print, you'll most likely find wording like:

"This appliance is intended to be used only for supplemental heat.
(copied from a Temco vent-free fireplace manual).


#66: Author of letter #65 again: Manufacturer speaks with forked tongue?
Date: Friday, February 24, 2006

I didn't have my manual so I called the company and they claim it can be run 24 hours a day. Its a Desa Comfort Glow blue flame heater (CBP30T). I have a CO detector but it only starts reading at 30ppm. I don't have any moisture problems but do get a heavy film on the windows. Should I assume their advice (that I can run it constantly) is incorrect? Better said, is even possible that it is that safe?

Sweepy Hello again Victoria,
You can view the owner's manual for your Comfort Glow online by clicking
here. First, note pages 4-6, where it shows the required airflow into the room, and make sure your room ventilation complies (I'm betting it doesn't). Next, read the box at the top of page 7, where we find the predicted phrase, almost verbatim:
This heater is not for use as a primary heater, only for supplemental heat.


#67: Four pictures worth 1,000 words
Date: Monday, May 8, 2006

I was so pleased to find your site and have no idea why it didn't turn up when I searched before a couple of years ago. I'm in the process of trying to find out why my health made a rapid decline since I've been in the current house. The problems are headaches (which I have rarely ever had in the first 56 years of my life), bad lung problems, and memory loss problems.

It's a rental house and the landlord thinks vent-free is the only way to go. My suggestion that there could be a health risk met with an angry glare and avid support for vent-free safety. We don't have the option to move at this time since there are no rentals available within our price range, but we hope to find something before the next heating season.

I'm in the house 23 hours per day, most days during winter. The vent-free fireplace is the only heat source and runs continuously unless I turn it off. After turning it off, the living room quickly cools to 55º, a temperature that I can't tolerate at my age. On the days when the outside temperature is 20º or less, the fireplace doesn't even heat the living room.

The house isn't air tight, nor does it have any insulation, so we do have a fresh air source. Even so, just step in my living room and smell the fumes ... actually, walk up on the front porch and smell the fumes.

I have some sooting and a lot of gummy, shiny, brown residue almost everywhere, but worst on the wall behind the fireplace and on all the ceilings. There is also mold in various places, including all window sills. The windows are likely already ruined with fogging, which I didn't know about until reading your page today.

I'm washing walls today, preparing to paint and found your site while taking a break from the work. Here are some pictures, I thought you might like to see ... taken with my little web cam, so they aren't the best. You can see where I've cleaned: it doesn't take a lot of thought to realize what the inside of my lungs must look like.

Please note, the picture on the wall is brand new, just put up last week. The walls used to be just that white!!! Check out the first picture and notice how clean and white the lower wall looks, especially the baseboard ... and realize I have not yet cleaned the lower parts of the wall.

Thanks for a great site and wonderful info.

B. Nowak

Fireplace, rather pretty

Wall above fireplace,
after 1st cleaning

Wall above fireplace,
after 2nd cleaning

Corner Left of Fireplace,
not cleaned yet


#68: Soot-covered dreams: will the culprit step up to the plate?
Date: Wednesday, May 16, 2006

I have a home that is less than 1 year old. My husband and I installed ventless gas logs that were manufactured by DESA. We have soot all over our ceilings, walls, carpet, furniture, clothes....well you get the point. We called our gas company to come and check out the problem, and they told us that the wrong orifice was in the unit: it was for a natural gas unit and we have propane. The gas company sent the part to DESA . DESA came to our home and took photos, then took our unit to "test" in their lab. ( how convenient). We were told that they could not duplicate the problem, and that the orifice was not wrong. We have asked for our unit back with the original orifice, and a copy of their test report. We do not have it yet. We have been living with soot, soot everywhere: I just hope that the culprit of this problem steps up to the plate and takes care of the problem. Yes, I am probably dreaming, but remember-my dreams are covered with soot!!!

Sweepy Your gas company's technician was most likely mistaken about the orifice foulup. Propane is delivered under considerably greater pressure than natural gas, so propane burner orifices are quite a bit smaller than natural gas orifices. If you truly had a NG orifice in your propane fireplace, you'd have had flames shooting up about a foot tall!

Vent-free product manufacturers generally attribute sooting to improper log placement, improper air/fuel mixture, dirty orifices or burners, or airborne matter that hits the flames, like candle fumes, hairspray, etc. You don't mention which brand and model DESA fireplace you have, but here's an exerpt from the "Customer Awareness Sheet" for DESA's Vanguard VMH26 PR propane fireplace:

While heater is "ON", the following can produce soot:

* Burning candles or oil lamps of any kind
* Burning incense
* Cigarette, cigar or pipe smoke
* Incorrectly placed logs causing flames to contact logs
* Objects placed in or near the flames of your heater
* Burner air inlet or pilot burner dirty with dust, dirt, lint or pet hair
* Running ceiling fans or other drafty conditions. This can disturb the normal flame patterns in your heater

In the fine print on page 8 of the owner's manual, cleaning fluids and kerosene lamps are added to this list.

According to these documents, DESA says they're not responsible for soot damage if you burn candles, oil or kerosene lamps, tobacco or incense, if you have fans or drafts that cause air movement around the fireplace, if your logs get bumped out of position, or if there is ever any dust, dirt, lint, pet hair or cleaning product fumes present in your home that might be drawn into the burner inlet or pilot burner.

In other words, if yours is a normal household, DESA says your vent-free fireplace can cause sooting. And if DESA's owner's manual and customer awareness sheet can stand up to legal scrutiny, they're off the hook for any damage caused. This disclaimer, common in the vent-free industry, is unconscionable, and should be tested in court. C'mon now, what reasonable juror would allow the manufacturer's insistence that the home be free of CLEANING FLUIDS?

In our opinion, another "culprit" to go after might be your dealer. It sounds like he or she didn't inform you about all the things that can cause sooting with vent-frees prior to the sale, to enable you to make an informed decision about installing a vent-free in the first place.


#69: "Quit knocking vent-frees, you MONEY-GRUBBING CROOKS!"
Date: Tuesday, May 23, 2006

Let me tell you one thing.....and one thing only.....YOU DON'T WANT TO SELL VENT FREE LOGS simply because they don't COST as much and you make more BANG on your buck installing and selling Vented Fireplaces!

What a joke about ALL THE MOISTURE....and opened windows! IF....IF.....and that's a big IF....about opened windows! I've owned a free standing vent free fireplace....the logs burn beautifully....helped MY HEATING BILL TREMENDOUSLY....and I've NEVER....NEVER....had a problem with moisture nor have I had a problem with dangerous gases! I have sensors in my house and NOT ONCE...not once have they gone off. YES...I plan on keeping the sensors in my house and I have three for safety (even if I didn't have a vent free fireplace)

But I suppose, you'll SCARE OFF more idiot type people so they have to go to installers/sellers of vented systems....WHICH IS BIG BUCKS! Face it, you know and I know....I can put in a free standing fireplace....but more than likely....when YOU SELL YOUR VENTED FIREPLACES....YOU INSTALL THEM TOO! What a joke!

By the way....don't say alot of states in United States don't allow for Vent Free ...... why don't you tell them the FACTS! There are only THREE STATES....California/Minnesota/and Wisconsin that don't allow these vent free logs! But, don't fail to mention...California probably don't need the heat....Minnesota/Wisconsin is lagging in legistration on passing they too will join the rest of the STATES in allowing for a product that companies are fully satisfied to put on the market because THEY TOO....wouldn't want lawsuits that would cost them big dallors!

Why don't you tell the people how many....people die from there cookstoves/conventional stoves.....compared to these vent free gas logs! You can't....because if it was/is so dangerous....the GOVERNMENT would be bigtime against them!

Your article makes me laugh....trying to scare YOUR BUSINESS can survive!

Another thing for your thoughts! Ask a plumber if he likes installing plastic plumbing and he'll tell you COPPER is the way to go!! Why? More man hours.....costly materials.....and MORE MONEY FOR HIM!

Keep selling the dumb people that get scared off about Vent Free Logs.....they'll easily be sold your product along with dipping into there pockets for SEVERAL THOUSANDS OF can take from them! Bet with all the money you can leave your windows open....while these sheep come knocking down your door to have you install vented systems that PUSH ALL THE HEAT OUTDOORS!


P.S. You didn't sell me on your Vented Logs.....I've been saving lots of money with my Vent Free, you won't get my money

Sweepy Hi Dominico,

Calm down.

Open a window.

Take a couple deep breaths of fresh air.

Feel better?

We understand you're defensive about your vent-free gas logs, but man, you seem WAY too angry about it. And more than just a little misinformed. For the record, here are a few of the facts you've got wrong:

1) This is an internet website. Our customers are all over the world. We don't install the products we sell here, and, except for a few products that offer proprietary venting kits, we don't even offer venting for sale. In other words, we don't profit from the fact that the gas products sold here at The Chimney Sweep Online are vented.

2) We didn't build our business based upon our stand against vent-frees: our business has "survived" far longer than vent-frees have been available. Truth be told, we'd probably make a lot more money if we did sell vent-frees. We just don't think we'd sleep as well.

3) There are plenty of others with concerns about vent-frees who aren't trying to "get your money." If you read the letters on this page and follow the links at the bottom, you'll find a sizable list, including:

Indoor Air Quality Scientists
Consumer Reports Magazine
The American Lung Association
The Center for Disease Control
The Environmental Protection Agency
The Mayo Clinic
The vent-free owners who wrote the complaint letters on this page

4) Nowhere on this website do we say that "alot" of states have outlawed vent-frees: we mention the same three states you do, as well as Massachusetts and Montana. And New York City. And some counties in Arizona, Colorado, Washington, Kansas, Wyoming, Ohio, Michigan, North Dakota, South Dakota, Nevada, New Mexico, Alaska, Minnesota, Texas and New Hampshire. And the entire countries of Canada, Australia and New Zealand. Anyway, we don't even try to make the argument that vent-frees are a bad idea just because they're illegal in some places. Cigarette smoking is legal in all 50 states. That doesn't mean it's a good idea.

5) California didn't ban vent-frees because Californians "don't need the heat."

6) Vented gas systems don't "push all the heat outdoors." Millions of families heat their houses with them.

7) We don't know where you got the impression that we're in favor of unvented cookstoves. We're not. In fact, all the gas ranges we sell have built-in exhaust hoods. And since you dragged the government into your argument, you should know that several states have already passed legislation requiring outside-venting exhaust hoods for all new gas range installations. We expect that trend to go national, and we're behind it 100%.

8) Copper plumbing IS better than PVC plumbing for most applications, and costs less in the long run.

9) "Dallors" is spelled Dollars.


#70: Suffering from the "Fireplace Flu"
Date: Friday, June 1, 2006

What a wonderful site. I've been wondering if we're the only family having this problem with their ventless fireplace.

We purchased a "propane log" ventless fireplace from Lowes about 3 years ago. We loved the money we saved in fuel bills with our ventless fireplace but my husband especially had developed flu symptoms during the winter while we used the fireplace. I too had been bothered by all the soot that was being dispersed around the house but blew it off, thinking maybe I was becoming allergic to our cats. It took way too long for me to realize that I always felt good while I was at work but as soon as I got home the symptoms started. Headache, burning eyes, scratchy throat, runny nose, basically all the symptoms that would lead one to believe they had the flu.

I told my husband it wasn't natural to feel this bad all the time, and couldn't figure out why were we having all the flu symptoms, especially after we had flu shots. We had had no problems with colds and the flu since we started getting flu shots, until after we installed the ventless fireplace: now we were experiencing these symptoms all the time. My husband especially was going to the doctor quite frequently for relief from his symptoms. Now that it's warm and we aren't using the fireplace we're much healthier.

Wall above fireplace with pictures removed

Obviously, this isn't a SOOT detector

A year and a half ago I repainted our walls, thinking they were just dull from kids and not being painted for awhile. I'm sending pictures to show what damage was done by all the soot put off by our ventless fireplace so that others can see the damage done. You really don't realize it until its too late. My husband tried to talk to someone at Lowe's where we purchased the propane log and fireplace insert, but the person on the other end of the line only got frustrated (as did my husband) and the call was ended.

It's time for my yearly checkup and I'm going to mention our health problems to my doctor to see what he thinks, especially since I have developed chest pain and shortness of breath. I've never smoked, so problems with my lungs would be something I thought I would never have to worry about. I pray there's no damage done that can't be fixed by breathing clean fresh air!!

I hope many people read your site before they make the decision to go with a vent-free fireplace.

Thanks for listening,


#71: Author of letter #67 revisits
Date: Saturday, June 2, 2006

I had to laugh a bit at Dominico's irate and irresponsible comments about you and the site (see Letter #69 above). Obviously, he wasn't really reading the letters from all of us!

If he had left an email address, I'd have invited him to go with me to the doctor to learn about the medication I'm on now to handle my lung problems and to accompany me to the lung specialist's office on the 23rd of this month.

I can only wish him the best and that he doesn't end up with bad lung problems from his own unvented heater.

B. Nowak


#72: Another guest appearance from our old friends Headache, Nausea and Sooting
Date: Monday, June 19, 2006

My husband and I have a new-construction home (3 years old) and did not realize that the builder was installing a vent-free gas fireplace. We have some minor sooting issues (probably also related to candles) and I have felt nauseated and had headaches at times when the fireplace was on.

We would like to replace the fireplace with a vented model. We like using the fireplace because the vaulted ceilings, combined with a large number of windows, cause the room to be cooler than is comfortable for us. The area for the fireplace is at the corner of the home (vaulted ceiling extending to roof) and above the fireplace is an opening to hold our television. It would seem our only option is to have a side vent versus a chimney style vent. Is that correct? Also how labor intensive/expensive is something like this to do? Is there any benefit to getting a "sealed" gas fireplace - the kind with the glass in the front versus the "standard" vented model? We do have pictures of the fireplace area before the drywall was installed - is there anything I should look for?

Noel E.
Bartlett, TN

Sweepy Because of your television, a direct vent installation out the sidewall or a vertical vent installation with the pipe extending to the roof behind the televeision opening will be two options. Direct vent fireplaces are the ones with sealed fronts, and are the most efficient type of vented fireplace. All of our gas fireplaces are direct vent.


#73: Air filter completely permeated with soot
Date: Tuesday, July 18, 2006

Just like so many above, I have an awful story to share about my first (and last) experience with an unvented fireplace. I bought a new home in August of 2005. It featured a vent-free propane fireplace in the living room. The builder told me the unvented fireplace was an ideal way to supplement my heat-pump during the coldest months of winter.

It seemed like a wonderful idea at first, but after just one winter, the walls and ceilings of my entire home are stained with soot. The studs, spackled joints, and the drywall nails are highlighted with gray stains. White kitchen appliances had to be scrubbed, and even the carpets are stained in the corners and around the edges of the walls.

The reality of the situation really struck me when I changed the filter on my CPAP machine (constant positive air-pressure machine: a medical device used to assist my breathing and prevent sleep apnea at night). The normally bright white filter typically collects a thin coating of gray dust over the course of a few months. But this time, it was absolutely black: completely permeated with soot…and it was located in my bedroom at the furthest opposite end of my house from where the fireplace is.

I’m just sick about the whole thing, but a little comforted to learn that “I’m not the only one” to deal with this. With the help of what I’ve read on your site, I’ll be looking into insurance, and maybe even legal remedies. And I’ll definitely be replacing my unvented fireplace with a cleaner, healthier heat source before winter of 2006.

Lee Davis
Leicester, NC


#74: To vent, or not to vent?
Date: Tuesday, August 8, 2006

I am so fortunate to have found your site before I listened to the plumber and purchased vent free logs. I had called him in to give me an estimate for a vented unit!

It is criminal that peoples' health is being destroyed because our laws do not protect them from the capitalistic pursuits of the corporate class!

Thank you for the life-saving heads-up!

Lisa Charmont
Metuchen, NJ


#75: Greasy film on windows (and in lungs?)
Date: Saturday, September 16, 2006

Thank God & greyhound for your web site! Every dealer I have been to says go with ventless...the only other thing I had heard in the negative; my Dad ended up with a greasy film on all 32 of the windows in his solarium. And it doesn't come off easily. Often wondered what ended up in his lungs.

Here's my problem. I would like a propane fireplace on an interior wall. I'd rather not vent upward, that would mean building a false wall for the pipe work. (There's a bathroom on the other side of that living room wall.) My house however, is built on 4' pilings and is completely open underneath with the exception of the underpinning that conceals the pipes and electrical goodies. Is it possible to "down-vent"? I never hear it refered to. If so, I'm assuming some kind of electrical device is needed to draw the air in and the bad stuff down and out.

Only one dealer I spoke with ever heard of a fireplace made this way and he didn't know a lot about it. Said it would be as much to buy the fireplace as it would be to build that false wall and install a regular one. Cost is a factor, but safety and ease of installation would win out.

Once again, thanks so much for your knowledge and availabilty. Even the "usepropane" site didn't have much to offer.

M'Liss Miller

SweepyThanks for the inquiry, and for the kind words about our website! Unfortunately, we don't know of any gas fireplaces that can vent downward. It shouldn't be a big expense to "chase in" the vertical vent pipe, though. This wouldn't necessarily require a false wall, or even a chase as wide as the fireplace: just an enclosure large enough to hide the pipe while providing the required 1" clearance all around. Many traditional masonry fireplaces have been installed this way, with the chimney "bumped out" into the room, so it would lend a look of authenticity to your installation. Your venting enclosure could be framed with standard 2x4's, then sheetrocked and painted to match the walls in the room, or finished with brick, brickette, stone or tile to match the fireplace facia.


#76: Another Hearth Product retailer drops vent-frees
Date: Monday, September 25, 2006

It is great to come to your site and read all of the customer feedback!!! I have worked for a retailer in the hearth product industry in Maryland for about five years now. Before working here I had no idea how much was involved in fireplaces, between getting the right look to getting the right amount of heat there are just so many options.

My boss decided to discontinue selling vent free appliances about two years ago. My thoughts were mixed. I had read many things about the adverse affects of vent free, but it wasn’t until I read the negative testimonies of so many consumers that I became thoroughly convinced that vent-frees are not products I would want to sell.

Thank you for your web site and thank you to the consumers for their statements as well.

Sales at FiresideStone


#77: Has "gotten sick" from vent-free gas logs: do they have to remain vent-free?
Date: Sunday, October 1, 2006

Q: I have a vent free gas log set installed in an existing wood burning fireplace with a chimney. Will opening the flue all the way eliminate the health risks associated with vent free products? I have gotten sick and will not run it again unless there is a safe way. I am not worried about heat loss either.

Carl Johnson

Sweepy Some vent-free gas log sets are in a metal enclosure that blocks the flow up the fireplace chimney. If yours is one of those, opening the damper won't do you much good. If your gas logs are open at the top, however, and there's a clear path through the fireplace damper, it would be a great idea to open that damper every time you burn the logs.


#78: Brown walls from occasional vent-free use: a call for a class action lawsuit
Date: Thursday, October 5, 2006

In the end of 2000 I purchased a vent free gas logset mainly for power outages. We have bad ice storms and power outages lasting sometimes 5 to 7 days. We had an outage for 5 days, and we used the gas logs 24 hours per day, as they were our only back-up heat source. All the ceilings in the rooms that were opened are destroyed. When I wipe the walls the towel is brown. I am positive the gas logs did it, because the closer you get to them the damage is worse. Right over the mantle that the logs are in the ceiling is almost brown. This home was completely remodeled in 2000 and now over half of it has to be redone.

Has anyone on this site gotten any satisfaction from the manufacturers of these products? When I called them, they asked me what did I want them to do and in the same breath told me there was nothing they could do about it. So the gas logs are now boxed up. The cost was over $1000.00 for a product that was destroying my home. Not to mention the repair bills I will have. Seems like someone would have started some class action lawsuits.


#79: Moist heat, funny smell, possibly causing headaches: are the dogs safe?
Date: Monday, October 16, 2006

I am really glad I stumbled on this site. My husband installed a ventless propane fireplace in the spring. We only used it a couple times in the spring and just recently had it on for about 4 hours one evening.

I told my husband in the spring that it had a sort of funny odor, but not really propane, he said it was nothing to worry about. We have a digital CO detector just a few feet away from it (which has never gone off). We have another one in the kitchen which is also just a few feet away (it has never gone off). We have this fireplace in a room that is approximately 12 x 22 (small room). This fireplace is just for the ambiance of it all, not a heat source even though it heats up the room quickly unless kept on low.

I always feel as though it is a moist kind of heat with a funny smell. I have gotten a headache once or twice, but am not sure it is the fireplace. I am more worried about my two 9 pound dogs. Do you think that using it occasionally (once or twice a weekend, with the door to the outside slightly cracked open for ventilation, this door is a few feet away from the fireplace), would be a problem for our health. I am so frightened now that I do not want to use it. It seems like such a waste. My husband said to run a small fan pulling air out of the door with a window slightly cracked in the kitchen, which would be pulling air right past the fireplace. We would still have the ambiance of the fire, but maybe not the dangerous fumes. I don't know what to think, do you have any thoughts on this? Thanks so much.

New York

Sweepy By all means, open the door and the window, but take care that the resulting breeze doesn't disturb the flames in your vent-free: air disturbance is one of the hide-behinds vent-free manufacturers use to excuse sooting.


#80: Open damper to stop wall stains
Date: Tuesday, November 14, 2006

I have a set of "ventless fireplace logs" installed in a regular wood-burning fireplace. This was for convenience. I am experiencing the wall stains as mentioned in so many of the letters on your site. Would simply opening the flue solve this problem? Or would this cause other problems being that it is designed to be ventless? I heard that possibly there is some "gizmo" to hold the flue open partially. Would this be something you can advise on? Thank you for your help.

Elizabeth Beach

Sweepy No need to prop your damper open permanently: just be sure and open it all the way whenever you fire up the gas logs.


#81: Direct Venting Options
Date: Tuesday, November 21, 2006

First off...thank you for this great site which confirms to me what I have preached to friends and family for years. Vent-free on the surface sounds too good to be true but as usual there are serious drawbacks.

I'm currently looking to put a direct-vent NG stove or fireplace into my finished basement which serves as family room / playroom for kids. The problem is that there's no room on the only exterior facing wall due to built-in closet, cabinets and computer desk. Is it possible to have a horizontal (or angled) run of vent to get to this exterior wall? If so how far a run? I've been unable to find a description of this type of installation and hope you'll have some experience or advice.
Thanks in advance,

Rob Noll
Wallingford, PA

Sweepy Some direct vent stoves can go quite a distance sideways if you can give them a little vertical rise first.


#82: Thought the vent-free was great (except for the filmy windows, yellowing walls, fatigue, memory loss & respiratory infection)
Date: Saturday, November 25, 2006

Q: We have heated our home for four years with an unvented gas log heater. The winters have been mild so we didn't have to turn on our furnace which is thirty years old. We thought the heat was great, although I hated the film on the windows and the yellowing or orange on all the walls.

But then it started to affect our health (I can see that now). For over a year I was so tired and fatigued and couldn't figure out why, and every time my husband sat down in a chair he was falling asleep. Then in Jan. 2006, I had a respiratory infection which left me with a cough. I have been doctoring for six months and every test came back okay, even had an angiogram, and it was fine. My husband has suffered with a loss of short term memory. The day I was taking him to the neurologist, our unvented gas log heater started to put out a smoky, sooty smell. I couldn't stand it, so we turned it off. When we came home I found your site on the internet.

We haven't turned the gas log heater back on and both of us feel 100% better. I have had a hard time getting people to believe me. I called our state health department and they shoved me off on our county health department. The woman had never heard of any problems with gas log heaters, told me they were safe. She told me to call poison control and the woman I talked to there would not even listen to me. Told me gas log heaters are completely safe and I shouldn't believe everything I read on the internet.

The only person who believed me was the woman at Service Master, when I called to find out what their price was to help me clean the house. They sent two woman to help me wash walls, ceilings, woodwork, everything.

Has anyone complained about stirring up the stuff that is on the walls and ceiling? One of the women started coughing and the other one got a headache.

I do plan to paint everything and I'm hoping that it will seal the walls and ceilings. Can anyone give me any suggestions about clean up?

Thank you again for your site.
Judi VanMeerten

Sweepy Go easy on your health department and poison control personnel, it is likely they haven't had much experience with vent-free gas appliance problems: direct vent gas products are a fairly recent idea, and there are relatively few of them in service as compared to vented gas products. I called our County health department about vent-frees a short while back, and nobody in the office had even heard of them. Most consumer complaints go to the vent-free dealers and manufacturers, who understandably have little motivation to publicize them.

Gas exhaust soot contains super-tiny particles called PM 2.5's, which are so small it would take a couple hundred of them to cover the period at the end of this sentence. These particles are lightweight enough to be airborne, and small enough to bypass the upper respiratory system and lodge deep in the lungs. When cleaning up after a sooting incident, the safest way to limit inhalation of these particles is to work wet. Damp sponge, don't vacuum. Once you get the soot cleaned off, a good coat of paint should stop any remaining particles from entering your breathing space.


#83: Hearth Product Professional cites seller misinformation and consumer inaction as biggest vent-free problems
Date: Thursday, December 7, 2006

Our company has now removed well over 350 vent-free (room vented) products and replaced them with direct vents.

It seems no matter how many vent-free products that get replaced, and no matter how many complaining vent-free owners there are, the consumer is still being misled about room-vented gas appliances. Between "Loewes knows" and the popular conception that the gas company would not sell anything that would hurt you or your home, there is so much misinformation out there it is hard for the consumer to know what to do.

Much of this misinformation originates on the showroom floors of vent-free dealers. It seems to me that the training for vent-free sales clerks must include the following instructions:

Don't mention that there are 3 types of gas products; vent-free, gravity vented and direct vented. Our pitch is all about vent-frees.

Keep stressing the 99.9% heating efficiency, which deflects attention from the fact that vent-frees are not supposed to be used as primary heaters.

Gloss over sizing guidelines and room ventilation requirements. The consumer might be smart enough to figure out that an open window is not too bright when you're trying to heat your home.

Address moisture issues on a positive note: "In dry Winter months, a little humidity is good for you." Never mention water running off windows and walls, mold, mildew, rot, or moisture-related health problems.

Don't mention that you can't install a vent-free product too close to a ceiling fan or a window, or a return air duct, or an outside door, or in a bedroom or bath. If you do, the consumer might figure out a vent-free product is not the best choice for their family and home.

What the buying public SHOULD be made aware of is that when the vent-free product creates a problem it will always be the fault of the consumer. If the vent-free product is used to heat, the manufacturer can call that abuse and misuse of the product. If the vent-free product is too large for the area in which it is installed, it is the consumer's fault, even though the consumer was not told about proper sizing. The list can go on and on.

It seems because we don’t have a room full of body bags, nobody wants to listen, as if it's not a big problem. I believe that sooted-up homes, water running off windows and walls, headaches and sinus problems, burned-up mantels, discolored walls and film all over windows are a big problem. If anyone with a vent-free has had any of these problems, email the consumer safety product commission at Also email and let the code guys know about your vent-free issues. Then call your newspaper and tv station. Let’s get the truth out.

Perry Bumpers
Fireplace creations by BMC


#84: Upright citizen no longer leaning towards vent-frees
Date: Tuesday, December 12, 2006

So glad to find you and the information you have about vent-frees. I was leaning toward a vent-free until I read about the subject on your website. I guess for the amount of time I would use the gas fireplace I don't want to take a chance on all the unsavory things that could happen.

Thank you for the information.
S Voorhees


#85: Pregnant friend feels "tired" when using borrowed vent-free
Date: Wednesday, December 20, 2006

I own a 30,000 btu Comfort Glow vent-free LP heater. I used it to heat a small studio apartment for over a year. I went from a $150 a month (winter) electric bill to a $20 electric + $50 LP monthly cost. Less than half the cost of electric alone.

I did smell an "odor" and so did my guests but I got used to it after a week or so. It smelled faintly like a bbq but was not offensive. There was no soot and I had no excess moisture around my single pane windows. I had a CO alarm installed right under the unit and never once did it go off from the heater. I set it off once with a lighter and a jar to make sure it worked so I am confident there was not an elevated level of CO in my apartment due to this heater.

Since then I have bought a house and use a free standing gas log fireplace vented through the existing chimney and I am positive it is no where near as efficient as my old propane heater. I am considering installing the unit in my house but would like to be sure it is safe for my family and I. The only reason I am alarmed is I have a pregnant friend who claims to feel tired when using my heater which is on loan due to the recent storm power outages. I went to look for info on this subject and came across this site, and [the manufacturer's website, where I learned that my model has been discontinued]. There is no reason listed on the [manufacturer's] site [as to why my model has been discontinued] and they still sell different models but not mine. I see you have no letters from happy owners of the vent free heaters. Am I the only one?

Lon Jasper
Enumclaw, WA

Sweepy Lon, you mention you've been to our website, but I wonder if you actually read all the pages in our vent-free section.

If you had, you'd be aware that The American Lung Association, The Center for Disease Control, The Environmental Protection Agency and The Mayo Clinic all caution pregnant women against exposure to vent-free exhaust.

You would have learned that lethargy and fatigue are common symptoms of low-level CO2 poisoning, which might give you an insight as to why your friend feels "tired" when she uses your vent-free.

You would have learned that your CO detector is designed to warn you of life-threatening levels of CO in your breathing space, but that health professionals warn against regular exposure to much lower levels.

You might have figured out that the odor you finally got used to was the smell of the poisonous Carbon Monoxide, Carbon Dioxide and Nitrogen Dioxide emissions you (and now your friend) are breathing whenever the vent-free is in use.

You also say you've been to Comfort Glow's website. Did you miss the warning on Page 2 of Comfort Glow's Owner's Manual that reads: "Some people are more affected by carbon monoxide than others. These include pregnant women, people with heart or lung disease or anemia, those under the influence of alcohol, and those at high altitudes."?

In the same owner's manual, same page, Item 3, Comfort Glow states that "This appliance shall not be installed in a bedroom or bathroom." which means your vent-free isn't even on the menu for a studio apartment.

This is free country, and you're perfectly entitled to disregard safety warnings and expose yourself to whatever health dangers you choose: but if you're truly a friend to your pregnant friend, advise her to stop using that vent-free ASAP.


#86: Educated Consumer wants to vent
Date: Friday, December 22, 2006

Q: I have just finished reading most if not all of the posted letters and responses regarding vent free gas logs. Thank you for the forum, it has been an education.

I now understand it is necessary to open the damper when a vent free system has been installed in a wood burning fireplace. For those of us who have wood burning fireplaces, is there any reason not to replace burning wood in favor of installing a vent free system? It seems to me that gas vs. wood in a traditional fireplace (damper open) would favor gas. In my case, the fireplace is not used for heat, just for ambiance. My wife has been asking for this conversion for a while now and I was about to make this her big Christmas gift until I came across your forum during my research.

Thanks for your insights.

Happy Holidays,
Joe Gugel

Sweepy If you're going to vent your logset anyway, why not buy a vented set? Vented sets provide MUCH more realistic logs, flames and embers than vent-frees do. The star of our gas log show is the vented Portland Willamette Fiber Glow set, which may be viewed online by clicking here.


#87: Why don't vent-free manufacturers give us more information about safe operation?
Date: Saturday, January 27, 2007

Q: I've had a 99% efficient (as I'm told) gas burning vent-free fireplace for over 5 years. In my 6th year, I started feeling sick; headaches, coughing, lots of fluid in my lungs. I thought I had a cold or flu and went to the doctor.

When do people get sick from the flu?

When do people predominately use their fireplaces?
When it's cold.

Do you think it occured to my doctor to ask, "How's your vent-free fireplace feeling?"

After three visits, what I found out was the IRON level in my blood was rising! Wow. [Only then did I consider that my vent-free might be the culprit].

In a vent-free system, black residue (looks like smoke from a wood fire), means there is a problem, as it is a sign of improper or incomplete combustion. I finally noticed that the yellow bricks in my fireplace were turning black, and my gas flame was not blue but starting to turn yellow. That told me the fireplace was not adjusted correctly, so it was not burning at 99% efficiency and, as a result, causing my lungs and liver to work overtime. This was after three months of breathing all that good stuff.

I went back to the owner's manual and read all of the mumbo-jumbo legal stuff. But nowhere in the manual did it talk about the flame, which has got to be the 2nd most important thing the consumer should know about (exploding being #1). I could find nothing in the manual about the two major signs of improper combustion or how incomplete burning might affect the (99%) efficiency claim. I went to several vent-free manufacturers' web sites, downloaded the manuals in .PDF format and found nothing.

This issue could easily be resolved with a little customer education. The intelligent thing to do would be to publish information about the black residue and flame color in the owner's manual. The way I see it, the manufacturers don't want to increase their call volume, would rather let the local service tech figure out the problem. Meanwhile, the consumer suffers from the sickness and pays the medical bills.

Got any thoughts? Yes I have a Carbon Monoxide tester, down to 60ppm and working, tested it on my car.

Fairfax, VA
Go Raiders!!!!

Sweepy Hi John,

First, you need to get clear about vent-free efficiency claims, and the difference between combustion efficiency and heating efficiency. Vent-free manufacturers do not claim that their products burn the fuel at 99% efficiency. Their claim is about heating efficiency, which is just another way of saying that, when you burn a vent-free, you not only get the heat from the flames, but also the heat from the exhaust, because it vents right into your living space.

No matter how carefully you adjust your burner, you're never going to approach 99% combustion efficiency.

It seems vent-free manufacturers universally tend to avoid getting too specific about things like incomplete combustion and sooting (and the warning signs thereof), presumably because full disclosure might negatively impact sales. For example, if you dig down way deep in your manual, you might find that the manufacturer recommends a monthly professional cleaning and adjustment of your vent-free system throughout each heating season (which, if followed religiously, might have spared you at least two months of your high-level exposure). If this caveat were moved to the front page of the brochure, prospective buyers might just decide that the annual expense for this monthly service would negate any savings from going vent-free in the first place.

CO detectors are designed to protect you from a one-time exposure to lethal levels. If your CO detector is UL listed and manufactured after 2000, it won't register CO levels below 30ppm, and won't sound an alarm unless levels rise to 100ppm, or remain over 70ppm for an hour. In recent years, medical health professionals have become increasingly concerned about repeated or chronic exposure to much lower levels; OSHA, for example, prohibits CO levels over 35ppm in any workplace. If your home CO detector constantly registers 60ppm now that your vent-free is tuned up and burning properly, try to put in all the overtime at work you can: you'll be healthier for it.

And Carbon Monoxide (CO) levels don't tell the whole story. Chronic exposure to some of the other constituents of vent-free gas exhaust, such as Carbon Dioxide (CO2) and Nitrogen Dioxide (NO2), can also cause the symptoms you're experiencing. And this is when your vent-free is in proper adjustment.


#88: A "vent-free victim" tells her story
Date: Saturday, January 27, 2007

Wow, has your site been helpful! I've been having breathing and respiratory problems lately, much more than usual even though I have been treated for allergies all of my life. Today I was feeling especially bad and wanted to sleep all afternoon. Instead, I got out my Windex and started cleaning glass and windows inside my house. The cloth turned black where it wiped the window. I was puzzled so I cleaned another--same black residue. Hmmm. What was happening? We've had non-vented (propane) gas logs for about 3 years but had problems getting them adjusted so only this year started using them to supplement the central heating on really cold days. Someone else cleaned my house this past winter, so I had not seen the black residue. Had the gas logs caused the soot on the windows?

After a rather extended Google search, I found this site. I am now convinced that not only had the gas logs caused the soot, but, most likely, my respiratory problems, headaches and lethargy also. It's somehow reassuring since at least the problems won't get any worse now that we've turned off the gas. But I'm afraid that my lungs will never be the same. I plan to notify several entities--including our propane supplier, who recommended the unvented logs, our Texas Environmental Quality Commission, the gas log manufacturer and other appropriate agencies. Thank you so much for letting vent-free victims tell their stories.

Nan Rentz
Waco, Texas


#89: Thanks for the heads up
Date: Friday, February 9, 2007

I was considering getting a vent free fireplace, and thanks to your message board, I feel relieved I never ever ever made the choice. Thank you everyone who gave me the heads up!!!



#90: Can I switch to a Direct Vent?
Date: Monday, February 26, 2007

Hi, I have a vent-free fireplace and like so many others, found you guys when researching the smell [and other issues].

Can a Direct Vent insert be placed on my existing hearth and can I use my existing surround and mantel??

Roger Wilkerson

Sweepy Hi Roger,
The answers to your questions will depend upon the dimensions of your existing setup. To compare, click the thumbnail photos on our
Direct Vent Gas Fireplace page, then click the INSTALLATION SPECS button on each model's page for framing dimensions, venting info, etc. Tip: the fireplaces on our Gas Fireplace page are arranged by size, so if you determine that a given model won't fit your situation, check the one above it, and so on.


#91: Chronic bronchitis, sinus infections and soot: Charlotte has had enough
Date: Friday, March 2, 2007

Just finished reading the many letters on your [vent-free] stoves page. I have one, and it's the only heat I have in this old house. I can't begin to tell you how black things get in just a few days... my clothes are black , my tv screen, my windows, walls, and ceilings.

I get bronchitis often and have been sick with sinus infections for over 2 months now. I ran out of propane and said that's enough. Now I have to figure out another source of heat, since this old house never had a furnace of any kind. I never thought about [the vent-free stove] making me sick, but now that I look back it makes sense. I have been breathing all this soot for over 4 years! These terrible products need to be taken off the market.

Charlotte Ames

Sweepy Hi Charlotte,
Until the US adopts an indoor air quality standard, I'm afraid it is unlikely that vent-free products will be taken off the market. But whoever sold you a vent-free stove as the sole source of heat for your house should be run out of hearth product business. Even the vent-free product manufacturers themselves will tell you vent-frees are ONLY for supplementary use a couple of hours per day with a window open.


#92: Loves having a gas fireplace; not so keen on odor, headaches & sooting
Date: Friday, March 9, 2007

We have been having some of the problems as described in your library. We just bought this house and Love having a gas fireplace. However, we have noticed an odor coming from the fireplace and I have been suffering from headaches. Not to mention all of the Soot all over the place.

Could you direct me to someplace where I can find information on the fireplace to see if it is able to convert to a vented model? My husband seems to think this is possible. Here is the make and model of our fireplace:

CFM Harris Systems Inc. Model UE-241L S/N 8365

Any information you could give us would be helpful.

Carol Hastings
Rising Sun, MD

Sweepy Hi Carol,

Good news! You don't have a vent-free fireplace. What you have is a model UE-241L vent-free LOGSET. These were designed to be installed inside an existing fireplace, to convert the fireplace to vent-free operation.

The UE-241L vent-free logset was manufactured by a division of CFM Corporation, which markets vent-free products under several brand names. Assuming the fireplace your vent-free logset is installed in has a chimney, it might be possible to vent the exhaust by opening the fireplace damper. Consult with CFM to see if that option is allowed. If it isn't, you can always remove the vent-free logset assembly and install a vented logset.


#93: Home Inspector involved in mold spore litigation; suspects vent-free fireplace is at fault
Date: Monday, April 9, 2007

Thanks for the amazing amount of information on your website regarding unvented heating equipment. I appreciate the work and time you put into it.

I am a home inspector with 10 years experience and probably 4000 or more homes inspected, and your views precisely match the advice I give to clients whose prospective homes include any unvented equipment.

To get to the point, I am involved in litigation with a client that purchased a home that included an unvented propane fireplace. The fireplace is not the problem as such, but resulting excess humidity that resulted in potential mold growth is the issue. Are you aware of a web source for information regarding more the humidity/mold risk rather than the combustion by-products issue? I am aware of how closely related the symptoms of CO and CO2/NO2 poisoning can be to mold sensitivity.

Thanks for any help you can offer me in this regard. And again, thanks for the time and trouble you invest in this area for consumers.

Steve Kaple

Sweepy Hi Steve,
Thanks for the kind words! You'll find a good overview of the causes and symptoms of household mold spore poisoning, along with dozens of links to other sites with pertinent information on the
Health and Energy website.


#94: Sooting, coughing, headaches lead to decision to replace vent-free
Date: Friday, May 4, 2007

Oh, boy does this this information hit home! I cannot tell you how many times the walls and ceiling have been done; they're a sooty mess. I thought we had the black mold! Now I know differently. After experiencing constant coughing and headaches, we're contacting the fire department to have them investigate CO poisoning. I believe this [vent free fireplace] should be replaced immediately. THANK YOU.



#95: House covered in black soot, won't use vent-free gas logs again
Date: Thursday, June 21, 2007

I have been reading your emails concerning vent free logs. I too have had ny whole house covered in black soot and will not burn my vent-free gas logs anymore. But I understand vented gas logs are not very efficient. Doesn't most of the heat go out the vent? And with the cost of propane it could be very expensive? If I am incorrect please let me know while I am deciding what kind of heat to use.

Terry E Thompson

Sweepy Hi Terry,
There is a difference between
vented gas logs, which are installed in an existing fireplace primarily for looks, and vented gas inserts, which are designed to heat. Today's direct vent gas inserts achieve efficiency scores up to 86%, and are designed to heat the entire house.


#96: A Gold Star for the Sweep!
Date: Saturday, September 29, 2007

I have read all the letters regarding vent-free logs and am convinced I need to rid our home of this product. I have a wood burning fireplace in which I placed the aforementioned vent free logs (mine are propane). Question: Are there direct-vent products that are adaptable to a woodburning fireplace? If not, are there any advantages to changing to a vented model versus using the vent-free model with the damper open? You deserve a "Gold Star" for the extremely informational and very helpful website!

Linda G.

Sweepy Hi Linda,
Thanks for the inquiry, and for the kind words about our website! One problem with vent-free gas logs is, they're designed to deliver the heat into the room via the hot exhaust: open the damper to vent the exhaust, and all the heat goes out the chimney.

If you want meaningful heat without breathing gas exhaust, the solution here would be a direct-vent gas insert. These draw their combustion air down from the top of the chimney through one pipe and send their exhaust back out with another pipe, so they don't affect your breathing air at all. And they deliver heat at over 80% efficiency!


#97: Installing company admits odors and sooting are "normal"
Date: Friday, October 19, 2007

I have a question that no one has been able to answer yet. We have a gas fireplace that has been a miserable experience so far. The "exhaust" from the fire comes into our house instead of going up the chimney. When it is on the entire house smells of gas (esp.on the 2nd floor, the fireplace is on the 1st floor) and it has left our ceilings and walls with a black, greasy film. This can't be right yet the company who put it in says this is normal. It can't possibly be! We have not used it in a year because I haven't trusted anyone to give us a straight answer.

Thank you so much!!!
Hilary Coughlin

Sweepy Hi Hilary,
I hate to break it to you, but your installing company is (belatedly) telling you the truth: the fireplace they installed for you is a vent-free model, and if the other letters on this page are any indication, the odors and sooting you're experiencing are indeed normal. If you want to have a fireplace you can actually use, you'll need to replace your vent-free with a vented fireplace.


#98: Can you direct vent a vent free?
Date: Tuesday, November 6, 2007

Moved into house year and half ago. Used to have wood burning as well as vented natural gas (old style chimney) fireplaces. This house had a vent free fireplace, never had one so figured hey there are so many must be ok. It is terrible. Used it once for a few hours and the room just smells so bad. Is it possible to convert a vent free fireplace ( looks nice) to a vented one , without having to go up.. can get to outside going right angle left about 10 ft.

Hope to hear from you when you have the opportunity.

Sweepy Hi Allan,

Sorry to say, even the very few vent-frees we know of that are cross-listed for vented installation need a vertical vent through the roof if you go for that option. If you must vent through a sidewall, you'll need to replace the vent-free with a direct vent model.


#99: Can I drill out my vent-free burner tube?
Date: Sunday, December 16, 2007

Hi, I replaced my wood burning fireplace with a vent free log set. The heat is wonderful but the smell is terrible !!!! And yes, it smells up the whole house. I thought it was the log set, so after two years replaced with another set and same problem!!! When I open my damper, of course the smell is gone but I don't get much heat. My question is, do vented log sets have more heat from them? My vent-free logs are rated 10,000 to 39,000 btu's. Or would it help if I drilled more very small holes in the flame tube? I'd appreciate your help. Great site you have, keep up good work,

Steve S
St. Louis, Mo.

Sweepy Hi Steve,

DO NOT alter the burner tube in any way. Vent-frees are finely tuned, and any change that drastic will almost certainly have dire consequences. Vented gas logs provide some heat, but are primarily decorative: if you truly want meaningful heat without the drawbacks of vent-free logs, you might want to consider a direct vent insert.


#100: New Vent-Free irritates wife
Date: Tuesday, December 18, 2007

I recently purchased a Procom Blue Flame vent free heater (30,000 btu). My house is old and not very air tight at all. I have a natural gas furnace and use the vent-free as supplemental heat.

I don't feel any ill side affects but my wife is another story. Since we started using the vent-free she has had a burning sensation in her nose and throat. I'm thinking this could be caused by the heater as a result of the "acid rain" ?????


Sweepy Hi Russ,

One of the by-products of the combustion of gas is airborne nitric acid. Even in very small quantities, this powerful acid is known to irritate "wet" tissues like eyes, noses and throats. Reportedly, some vent-free users actually experience nosebleeds.

Some people are more sensitive to vent-free exhaust in the home than others. To see if your wife might be one of those folks, try discontinuing use of your vent-free for a week or so and see if her irritation clears up. If it does, it sounds like you might have to choose between a vented fireplace and a new wife!


#101: Vent-free owner reports possible link to brain tumors
Date: Wednesday, January 2, 2008

Hello, I have a 22,000-39,000 BTU vent free natural gas fireplace and have been experiencing unexpected memory loss since I installed it about two years ago. It is in an approximately 340 sq ft room with two separate doors leading to the kitchen and the hall, which leads to three bedrooms. But at times I used to close both doors to the room and found it would heat the entire room at its lowest setting in 10-15 minutes or so. Anyway, in addition to the relatively sudden memory loss, I found I was often getting overcome by sleepiness (and thus taking naps, which I have never done) when reading in the room. I bought a carbon monoxide monitor about a year ago and plugged it into a wall socket in the room, but it has never emitted an alarm.

Any suggestions on what I might be able to do to test the air quality and test my own health? I am a mid-level executive in my company and have fairly regular health physicals, so I'm wondering if there are medical tests that can be run to detect levels of carbon monoxide in the blood.

I also have a slightly older brother who lived for two years or so in a small townhouse whose only source of heat was a vent free fireplace. While he was there, he began experiencing fatigue and memory loss and was diagnosed with a stage four brain tumor a year or so after moving out of the house. I have no evidence, but I have done a lot of research on the impact of decreased oxygen levels on the brain and resulting brain tumors, so I'm now beginning to wonder if there could be a connection between his tumor and the vent free heater.

Also, is there a way to vent the existing fireplace? It is installed in the middle of a living room on an inside wall. Can some type of vent be run through the wall and out through the attic? In the meantime, I will likely greatly cut back my use of the fireplace and lean more on the central gas heating system.

Thanks for your help. I'd also appreciate any other authoritative sources I could consult on the health impact of vent free natural gas fireplaces.

In Jesus and Mary,

Sweepy Hi David,

As noted above, your Carbon Monoxide detector won't sound an alarm until emergency life-threatening levels of Carbon Monoxide (CO) are present. It won't detect Carbon Dioxide (CO2) at all. The issue on the table is the possible consequenses of exposure to levels of these gases that are below the imminent life-threatening threshold, but still high enough to adversely impact your health over time.

Lethargy and fatigue are symptoms of both CO and CO2 exposure, so that could explain your need to nap. Both gases also interfere with oxygen transfer to the brain, which is known to cause headaches, confusion and memory loss. Your own research has evidently found another link we weren't aware of, to brain tumors.

There are tests for CO and CO2 levels in the blood, but they're not part of an ordinary physical: you need to specifically request them.

Here is the only one way we know of to safely vent your vent-free:

Disconnect the gasline.

Take your vent-free outside.

Leave it there.


#102: Feels like her head is in a plastic bag
Date: Tuesday, January 22, 2008

Q: We purchased our home in 1976. Nearly every year since, we have experienced flooding on our property, during which time we can't use our furnace and need an alternative source of heat. Our home was built with a wood burning fireplace, and we had a wood burning insert we used for years. My sinuses and allergies have deteriorated over those years, so we replaced the insert with a set of vent-free gas logs, which we had professionally installed. We have the damper closed and the chimney blocked, as per the manufacturer's instructions.

It is unbelievable how quickly the vent-free fire can change your breathing capacity. Frightening, actually. The moment the gas logs are lit I instantly feel like someone has put a plastic bag over my head. It is not a smell so much as a feeling. We only burn the logs as an alternate source of heat when we're flooded and cannot use our furnace, but the pilot light stayed lit most of the winter last year. Now I realize that these vent-free gas logs must be why I was ill all last winter. I first thought it may all be in my head, but then one day the control knob broke and the pilot light went out, and I began to feel better.

Because of the broken knob, we exchanged our original log set for a new set, also vent-free. As soon as my husband lit the new logs he experienced the plastic bag feeling too! I would go for a vented insert if I could be assured it would not affect us this way. They might cost more, but I do not want to feel like I'm dying and that is what I feel like when these logs are burning.

Thank you,
Carol Davis

Sweepy Hi Carol,

If you've read the letters above and followed the links at the bottom of the page, you've already learned that vent free fireplaces burn away the available oxygen in the room, and replace it with carbon monoxide, carbon dioxide, nitrogen dioxide and other gases. This depletes the oxygen supply, and your description of feeling like you have a plastic bag over your head certainly sounds like a reaction to oxygen deprivation!

Even the manufacturers themselves don't recommend vent-free products for people with allergies and sinus problems. Given the profound affect your vent-free logs have on you, I strongly urge you to make a change.

Vent-free inserts are designed to heat the room with their exhaust. Unblocking your chimney and opening the fireplace damper will siphon away the exhaust, which will make you breathe easier, but also take away the heat.

Since you really need backup heat in your situation, I recommend you replace the vent-free logs with a direct vent insert. These are sealed from the room, so they don't affect your oxygen supply: they get their combustion air down the chimney, and vent their exhaust out the chimney, leaving your house full of fresh air. The heat is delivered to the room via heat exchangers that are completely separate from the exhaust, so you get the heat without the poisonous fumes.


#103: Left the checkout line to check out vent-free safety
Date: Wednesday, January 6, 2008

Wow! I haven't even finished reading your entire page of letters from vent-free owners yet, but I am already so excited to have stumbled across this information. My husband and I have literally been at the store with a vent-free natural gas fireplace in our cart and walked away from it because we disagreed about its safety.

A decade ago, I was an office manager for a home inspection company in Upstate NY. I was in charge of typing up reports for the field agents who inspected each house for compliance to state-mandated safety codes. One of those codes required that any appliance which had a combustible means of operation had to be (A) properly installed with proper clearance from flammable materials and (B) had to be adequately VENTED (usually a vent pipe running a certain distance above the roofline and away from living space windows).

My husband, who just recently left a job where he worked alongside HVAC guys, said it was his understanding that the only difference between a vented fireplace and a vent-free fireplace is a removable, nozzle-type end fitting that screws on/off the gas line. Why do people remain so ignorant to the hazards and risks of vent-free products?

I'm now 100% convinced that I am right, and will use your website as ammunition to support my stand AGAINST vent-free units. I will definitely be shopping for a direct vent system! Thank you for preventing a lot of heartache, both emotional and physical, and for helping to ensure the safety of me and my family.

Keep up the great work - knowledge is power!
Ronda R. in Ohio


#104: Hearth product shop uninstalling vent-frees in multiple situations
Date: Monday, January 11, 2008

I actually work for a hearth products supplier/installer and have an installation crew at a job today uninstalling an unvented gas appliance. The customer put it in her home and cannot live with the smells she is getting. She tried using it but could not stand to have it operating. I am not nearly as knowledgeable as any of those making posts on this site, but have had customers want us to take them out in multiple situations.

As for heating, I would still love to see more info on the comparison between heating with gas furnaces vs. (vented) furnace-rated fireplaces.

Love your web-site.
Eric Spencer
The Fireplace Place, Inc.

Sweepy Hi Eric,
Thanks for the input, and for the kind words about our website! You can read one man's comparison between his forced-air furnace and his furnace-rated gas fireplace right here in our Sweep's Library by clicking


#105: Hearth product retailer has replaced over 400 vent-frees
Date: Tuesday, February 19, 2008

At this writing, our company has removed and replaced over 400 vent-frees with direct vents. We have many more customer who simply don't use their vent-frees, and tell us as soon as they save up the money they will have us replace them with direct vent models. The complaints are still the same:

Water running down windows and walls.
Soot all over home. EVEN IN THE REFRIGERATOR.
Yellow goo on walls and windows.
Headaches all the time when the fireplace is burning.
Children stay sick all winter [Doctor's advice: get rid of the vent-free fireplace].
House is full of mold & mildew.

Quote from a customer: " We were moving a bed from the north wall of our bed room. I could not believe it when we found a perfect outline of our headboard on our wall. ALL MOLD . Now we know why we were sick all the time. The man from the gas company told us it was from our vent-free logs. He said they cause sweat, especially on the north wall. "

Some good news: many of the largest builders in the US are now not allowing the use of vent-free products in their new homes.

More good news: there is currently a code change up for vote through the ICC INTERNATIONAL CODE COUNCIL [ FG47 ] to prohibit the use of vent-free [ROOM VENTED] fireplaces in all new site-built and manufactured homes that meet the air leakage requirements in section 402.5 of the ICC ENERGY CONSERVATION CODE. This would basically include all new construction.

In the meantime, why do we keep having these problems? We have great direct vent products now, many of them Heater Rated. Eliminate the doubt and stop the madness: CHOOSE A DIRECT VENT GAS PRODUCT.

Perry Bumpers
Fireplace Creations By BMC


#106: Never wants to live with a vent-free again
Date: Tuesday, April 29, 2008

I lived briefly in a rented house with a natural gas vent-free heater. The foul odor and reduction in air quality was apparent even when only the pilot was lit, and much worse when the heater came on.

To alleviate the air quality problem, I placed a portable room air filtration device equipped with a Hepa filter, a fan and an ionizer near the heater. Typically I kept the air cleaner running on low speed to eliminate the odor from the pilot, and I would turn it up to a higher speed when the heater came on. The vent-free was in a 4 seasons room with french doors, so I was also able to close it off from the rest of the house when I wanted to.

The homeowner had installed the vent-free and claimed to have never noticed the odor when he and his wife lived there previously. According to him, they left the french doors open and used it in conjuction with the forced air gas furnace to heat the entire house. They have since moved back in, presumably for life, and now have a young child. I wonder what kind of health challenges they might eventually develop, as they use the 4 seasons room regularly. After living there through only one heating season, I would never want to live with an unvented fuel burning device again.

Thank you for your expertise and willingness to be the best overall source of information for home heating products I have found on the internet.

Very truly yours,
Rick Sparks


#107: South African Dealer won't sell vent-free "rubbish"
Date: Monday, September 15, 2008

Bless you. We have been the only dealer for years in South Africa who refuses to sell vent free fireplaces because we have a conscience. We will use your site to convince as many clients as possible not to purchase this rubbish and use it to stop Architects from specing this unacceptable product. Yes they make money for the dealer, however there is more to life than money. Keep up the good work.

Wrex Trollope
Fireplace City
P.O. Box 1805, Durbanville
South Africa


#108: Vent-free Making us Sick
Date: Tuesday, October 28, 2008

Is there an option for converting a vent free Monessen fireplace to a vented? The vent free makes us sick.

Pamela Owen

Sweepy Hi Pamela,
I'm not sure if Monessen fireplaces can be vented, but here's their contact information so you can check at the source:

Monessen Hearth Systems
149 Cleveland Drive
Paris, Kentucky 40361 Phone: 859-987-0740
Toll Free: 800-867-0454
Fax: 877-867-1875


#109: What about our gas range?
Date: Saturday, November 15, 2008

Q: Hello, just came across your site, and am glad I did as I've been considering a Vent Free Fireplace or Heater. I read through a bunch of the Posts and they really are eye opening! Are there any Vent Free Heaters or Fireplace that don't kill you or your house?

Why don't Ovens and Cooktops put out Soot or CO, even on Turkey Day?

Thank you for your Reply.

Sweepy Hi Peter,

All vent-frees spew the same poisons into your breathing space: the only difference is the amount, which varies with the size of the burners.

The burners in ovens and cooktops are much smaller than the burners in vent-free fireplaces, and are tuned to burn blue, which is the cleanest, most efficient setting. Vent-free heaters and fireplaces are de-tuned to burn somewhat "dirty" so they'll produce yellow flames to better simulate a wood fire. Yellow flames = more soot and more CO emissions.

Aside from the de-tuning issue, the main difference between unvented gas cooking appliances and vent-free gas heaters is the amount of daily exhaust exposure. A household gas range produces the exhaust from an average of 6,400 btu of gas per day (this average is computed on an annual usage rate, and includes the peak usage season during the Holidays). Even if you limit usage of your vent-free to the recommended three hours per day, in those three hours a 25,000 btu vent-free introduces nearly twelve times as much exhaust into your breathing space!

Another factor about cooking with gas: these days, most gas ranges are installed with exhaust vent hoods, and more and more states now require them for all new installations. When used with an exhaust hood, a household gas range causes zero daily exhaust exposure.


#110: Can I turn my vent-free into a direct vent?
Date: Wednesday, December 3, 2008

I would appreciate your thoughts as to installing a direct vent on my vent free unit. My thought is to install one or two ports (3", 4" whatever would be the proper size) on the top of the stove; bring them into a Y 12' to 20" above the stove and vent to the exterior wall of the chase. Do you think it would be wise to drill two, three or more 1" holes in the lower part of the rear wall of the unit to bring in air other than room air? Maybe the front lower louvers should be blocked off so less room air is drawn in. The present unit is installed in a chase so it actually sits outside the room inside the chase. Hope to recieve your thoughts.

Thanks again,
Wayne Hunt

Sweepy Hi Wayne,

The short answer is, you're not going to be able to make your plan work. The intake and exhaust patterns in a direct vent fireplace are an enormously complex engineering feat, and require tightly sealed fireboxes, carefully designed intake and exhaust flow rate, combustion air preheat chambers and delivery ports that don't exist in your vent-free. There are many, many safety and performance considerations beyond that simplified overview, but the bottom line is, even trained professional engineers working from scratch (without the limitations presented by your existing vent-free firebox) don't come up with safe, functional direct vent designs every try.


#111: Does the color of the flame make a difference?
Date: Monday, January 5, 2009

I am reading all the bad stuff on your website about vent free gas fireplaces and how sooty they are. It’s true. We have one and it’s horrible. If I buy a propane heater that has a blue flame will I get the same soot? I pasted a picture of it below. Thanks for the totally awesome website. I believe everything you say about those ventless gas fireplaces…they are crap! Will I be getting myself into the same trouble if I buy the heater below to work with my propane?

Thanks so much for your time, I really appreciate it more than you can know.


Sweepy Hi Gen,

We don't recognize that heater, and can't read the label, but maybe we can answer your question anyway. If it is vented, you won't have any problems with sooting, excessive moisture or exhaust poisoning. If it is a vent-free, you'll be taking a step sideways.


#112: Add me to your list
Date: Tuesday, January 20, 2009

Add me to your unhappy vent-free owner page. I moved into my house in September 2008, and turned on the pilot to my propane vent-free logs in November. I noticed immediately that the mantel was sooting horribly even when the logs aren't lit. We recently had a cold spell, and I lit logs..... what a mistake! There is soot everywhere, even on my upstairs toilet. My question is, do I have to take out the logs or can I just turn off the gas? My filters were black and I will not ever use these logs again, I have three small children.

Also, can I switch to vented? I do not have a chimney. Thanks


Sweepy Hi Terri,

Permanently turning off the gas will absolutely eliminate your sooting problem. So will switching to a vented fireplace, but if you do that you will have to supply venting. This doesn't mean you need a chimney, though: today's direct vent fireplaces just need a short pipe through any outside wall, with a cap on the outside of the wall.


#113: Legal Recourse for vent-free victims?
Date: Monday, February 9, 2009

This is probably a silly question but is there not some legal action that can be taken in regards to the damage that vent-free gas fireplaces are causing? I also purchased one and my home is full of soot and I am getting headaches, this has been a cold winter and what a mess. I would appreciate any info that you can supply me with.

Thank you
Gail True

Sweepy Hi Gail,

Like yourself and most folks, we don't have the foggiest idea if damage from a vent-free is even actionable. It seems the vent-free manufacturers have gone to pretty extreme lengths to protect themselves in their literature: ie, Don't heat your house with the vent-free, Don't use it more than a couple of hours a day, Get it serviced every month, Always have a window open, Don't paint, recarpet or use any hairspray, candles or cleaning products, etc...

Why not give the family lawyer a jingle and get a professional legal opinion?


#114: Can Vent-Free be vented?
Date: Thursday, February 19, 2009

Currently have a see-through ventless fireplace which I do not use because of high oders, headaches etc. whenever I try to operate. Can I convert this unit to a vented unit or is it better to start with a new unit? I do have room to install a flue.

Thanks for your help,
Ray Bradshaw

Sweepy Hi Ray,

Only the manufacturer of your vent-free can tell you if it can be vented. Try a Google search and give them a shout. Even if your model allows this possiblility, you'd be far better off replacing it with a direct vent model. Once you vent a vent-free, you not only lose 90% or more of the heat produced by the fire, but also the heated air that gets drawn out of your house by the rising exhaust.


#115: Landlord puts Vent-Free in studio apartment
Date: Sunday, October 18, 2009

My landlord has installed a ventless gas heater in my studio apt. Any advice would be appreciated! I have not even turned it on for all the negative info I have read so far but they expect this to be my sole heating for the Winter.

Kim Amundsen (Kansas)

Sweepy Hi Kim,

You need to do a little research. Google the manufacturer and download an owner's manual for your model. We're betting you find your vent-free heater is not approved for installation in a sleeping room (studio apt), or as the sole source of heat for any apartment. If the landlord won't switch out the vent-free for a vented model, seek lodging elsewhere.


#116: How do we clean this sooty mess?
Date: Monday, October 30, 2009

Hello- I have been reading the letters on your website regarding the problems with the vent free products. I too have been experiencing terrible sooting all throughout my house. My question is this- how do you clean the soot? Is there a special product, or procedure for getting the walls clean? Thanks.

Julie Demo
Rochester, New York

Sweepy Hi Julie,

Here's one technique, published by Michigan State University Extension:

It is important that you carefully plan your clean up procedures in this process, especially when cleaning up soot, smoke residue or ashes from your fireplace. Soot, a carbonized deposit, can stain very quickly if liquefied through liquid chemical removal. Therefore, you want to remove as much smoke residue as you can through a dry method. Be aware that India ink, a permanent dye, is nothing more than carbon black mixed into a solvent medium. So be careful.

Your first step is vacuum, sweep, or wire brush the entire fireplace and surrounding affected area out. Be sure to use a quick 'flicking' motion with a brush and duster. Also,keep the vacuum head about 1/4 inch away from surface to avoid scratching. Wear old clothes, rubber gloves, a baseball cap, a disposable paper dust mask (available at any hardware store) and safety goggles during this process, especially when removing any loose particles. DO NOT RUB! If you start wiping down or rubbing this type of soil off with rags, the black pigment will smear and spread beyond your wildest imagination. Be sure to place newspapers under affected surfaces during this process so excess soot can fall on it and be disposed of easily.

Dry removal method requires buying a "professional" chemically treated soot sponge, available at janitorial supply stores (see links from this website). This tool is a 2" x 3" x 6" "special" dry chemically impregnated sponge which scoops up and absorbs dirt and soot into it's pores. Use until the sponge gets filthy dirty and then switch wiping area to a cleaner part of sponge. When it's filthy on all sides, remove surface layer by shaving off the dirty level with a razor blade to expose a new sponge surface. Do Not wring out the sponge with water or clean it or you will ruin the chemical treatment. When finished remove the newspapers carefully.

After you have removed as much of the smoke residue as possible with both vacuuming (dusting or brushing) and the dry, chemically treated sponge, then put down a plastic drop cloth and wash these same surfaces with a warm, mild solution of a water soluble citrus cleaner degreaser. Apply liberally, according to directions, onto surface and agitate with a hard bristle scrub brush. Be sure to use a plastic drop cloth under work area to avoid staining of unaffected areas. Wash and wipe down surfaces with a regular, wet sponge. Wash and wipe down surfaces with a clean, terry cloth towel. Then, rinse with water, and wipe dry again. If necessary, you may want to repeat "wet" procedure. After drying, you may wish to further "lighten" up brick work by dabbing onto the stone with a clean "normal" sponge a weak dilution of a bleach dilution mixed at 1 part bleach with 4 to 6 parts cool water. Bleach contains optional brightener and may bring out the accent of the brickwork even better.

Note: Always test an inconspicuous area for colorfastness, etc. before treating the exposed area. Also note that certain stains are permanent.


#117: Proper Ventilation for Vent Free?
Date: Monday, December 28, 2009

I live in a condo in Florida that has a vent free fireplace with natural gas logs. I run the fireplace for less than 2 hours but smell a gas odor and experience headaches whenever the logs are on. I do not know of any way to convert the fireplace to a vented unit as there is no chimney. Does running the "fan only" setting on my A/C help ventilate the fumes or opening a window? In FL, fireplaces are more for ambience than for heating purposes. I love the look of a fire but do not wish to make myself or my family ill.


Sweepy Hi Terry,
Don't run your AC fan; it will spread poisonous exhaust (and soot, if your fireplace drifts out of adjustment) all over your house. If you must use the vent-free, open a nearby window all the way.


#118: Sneezing Black Mucous
Date: Monday, January 18, 2010

I just found your site and it was such a relief. I bought an Empire brand vent-free propane stove for my new log home in 2006. I began using it that November, when it started getting cold here in Southern Illinois. For the first time in my life, I was besieged by sneezing atttacks, during which I expelled black mucous. I went back to the store and they told me to let the stove burn for a few days with windows open. That did not help. I suffered through repeated sneezing attacks, swollen and itchy eyes and headaches far worse than I had ever experienced. I used the stove throughout that Winter, and it turned everything in my house black, TV screens, computers, you name it. The air filters in the forced air furnace would turn black after about 30 days of use. I used the stove sparingly in 07 and 08, but it was bitter cold last month so I ran the stove quite a bit. Now I am so tired and listless, and my newly installed furnace filter is so black one cannot see thru it.

Do you know if any class action lawsuits have been filed in this issue?

Larry, in Ill.

Sweepy Hi Larry,
Still haven't heard of a class-action suit, and I'm a little surprised. When a small website like ours gets 118 letters complaining about vent-frees, it would seem to indicate some pretty widespread dissatisfaction. Why not pay a visit to a high-powered law firm and get the ball rolling yourself?


#119: Condensation Causes Mold, Sheetrock Damage
Date: Wednesday, February 3, 2010

Another dissatisfied consumer….I wish I could return our vent-free fireplace to the company who sold it to us and stick it where the sun don’t shine. It has taken us since we built our new home in 2003 to figure out what was causing all the condensation on our windows in the Winter. When I say condensation, I mean water running down the window panes in waves….we have had to repair sheetrock around our windows several times and also deal with mold. I don’t know what health problems this has caused besides high blood pressure, but I can say it has almost caused a divorce. Now that we know the problem, we have contacted a lawyer…we may not get anywhere but we are certainly going to check it out. These products should be against the law.

Dennis Olivier
Silsbee, Texas


#120: Persistant Odor, Evidence of CO Poisoning
Date: Friday, February 5, 2010

We're only wishing we had seen this website before installing a Superior vent-free fireplace in our new home. The fact sheet called it a truly safe, clean combustion, A.F.U.E. heater rated, 99.9% efficiency gas fireplace, equipped with back up safety features including built-in CO sensor and "Oxygen Depletion Sensor" system.

We always had a terrible odor when the fireplace was burning, and called the company we purchased it from to come back to look at it several times. Their technician made adjustments and at one time replaced the catalyst. Nothing seemed to make a difference, although they assured us it was safe to use.

My daughter was 1 year old at the time, and her cheeks would turn bright red. I now know that is a sign of carbon monoxide poisioning in small children.

About 6 years later we kept hearing a faint beeping sound from the fireplace. We replaced the battery but it still kept beeping. My husband called the company again, and was told that Superior had issued a bulletin in 2000 because the CO sensors were going bad in so many of these units, and the remedy was to remove it. He assured my husband it was only a backup safety feature and not needed.

Many years later, after starting the fireplace for the first time one season I ended up with heart palpitations and a terrible headache even with the windows open! When the EMT's came they tested the fireplace and immediately shut it down because of the high level of carbon monoxide.

We contacted the Consumer Product Safety Commission to file a report, and learned that there had been 33 other complaints filed on vent-free gas fireplaces between 98-08. They did not feel there were enough complaints to investigate further!

We also contacted Superior, who has since been bought out by Lennox. After much arguing they finally agreed to exchange our unit with a vented fireplace, but only if we paid for the installation and signed a release to keep them safe from any claims, lawsuits or damages. The release would also prevent us from disclosing any of the facts of the malfunction of the unit. Of course we did not sign!

We have not lit the fireplace since, but worry about future health problems for our children and ourselves from exposure to the vent-free poisons in our home for so many years. We can't understand how these fireplaces can be banned in many states and other countries, but continue to be sold in so many areas of the US today?

Karen Shaffer
Tecumseh, KS

Sweepy Hi Karen,
What we can't understand is that the Consumer Products Safety Commission claims they received only 33 complaints from 1998 to 2008, yet there are 110 complaints that we received in the same period of time right on this page!

Gentle readers, please continue to tell us of your vent-free experiences, but then click here to fill out a report with the Consumer Product Safety Commission, where it might do you the most good.


#121: Insurance Company won't cover vent-free sooting
Date: Friday, June 11, 2010

My company was called in recently to remove a vent-free fireplace and replace it with a direct vent unit. The vent-free had sooted the entire house! It was horrible. The soot had found its way into their forced air heating system and circulated throughout the house. We could see the outlines of the studs and rafters in all of the interior rooms. Soot was everywhere, even inside the kitchen cabinets. Heaven knows how much the homeowners inhaled. As they were giving me the tour of damage to their home, they informed me that their insurance company refused to cover the damage. The wife said that as soon as she told them there was soot in the house from a vent-free fireplace, the insurance company said, "We don't cover that." I have heard of insurance companies refusing to cover damage from vent-free fireplaces throughout the years, but this was the first time that I had heard such a negative response from a company without even sending an adjustor to investigate. The insurance company was not a fly-by-night organization, but a major insurance company. I cannot say I blame them at all, but the lack of insurance coverage with vent-free products should definitely be considered before a homeowner buys one. They could be the ones holding the bag and paying for whatever damage might ensue.

Jeff Smith
Area Manager
Today's Fireplace and Outdoor Rooms, Inc.
Wilmington, NC

Sweepy Hi Jeff,
Thanks for sharing! Makes one wonder just how many sooting claims it might take to cause a major insurance company to adopt such a strict refusal-to-pay policy, doesn't it?


#122: Will adding a "fresh air plus kit" stop vent-free sooting?
Date: Friday, September 24, 2010

Q: Need information on vent-free propane fresh air plus firebox and logset. Had a vent-free unit that sooted up entire house and now have a useless, but pretty, mantel. House is approx. 1800 sq. ft. very tight and well insulated. Can't vent outside due to it's being on inside wall - only place to put it. Can you help?

P.S. I was told that if I opened the window a crack, the soot would find it's way outside?

Nancy Wilson
Polk, OH

Sweepy Hi Nancy,
Your sooting problem occurred because the exhaust from all vent-frees, yours included, flows into the room, carrying the soot particals with it. It sounds like you've been told that adding a "fresh air plus" kit to a vent-free will alleviate that situation,
and that is not the case. The fresh air plus kit delivers outside air into the plenum surrounding the firebox, where it mingles with the already-polluted room air to "freshen" it a bit as it flows back into the room. The exhaust from the inner firebox, which is what caused your sooting problem, will continue to flow into the room unabated, just as it does now.


#123: Will opening the fireplace damper stop vent-free sooting?
Date: Monday, October 4, 2010

THANK YOU for providing this site. I wish that we had been aware of it before we purchased our vent-free fireplace. We have been trying for years to figure out why our walls and ceilings have soot-like streaks. We have washed and repainted and, of course, the soot has returned. Now we have the answer as to the source of the streaks and why our efforts were futile, thanks to you.

Our vent-free sits in our original wood burning fireplace. In lieu of pulling it out and replacing it with a vented version could we just open the damper some to eliminate the problem or would we lose too much heat? Thank you for your help.

Patty Thies

Sweepy Hi Patty,
I don't know what configuration your vent-free fireplace might be. If it is indeed a fireplace, with its own enclosure, installed inside your existing fireplace, opening the fireplace damper probably won't do you much good. If what you have is a set of vent-free gas logs, with no barrier between the fire and the fireplace damper, by all means open the damper all the way whenever you have a fire; your chimney should evacuate all the exhaust.

The bad news: since vent-frees are designed to transmit virtually all the heat to the room via the exhaust, evacuating the exhaust will also evacuate most of the heat from the fire, along with much heated air from the room. A direct-vent gas insert, which is designed to lose the least amount of heat via the exhaust, would be a much better choice.


#124: Landlord Visits This Page, Removes Vent-Frees
Date: Thursday, October 28, 2010

Hi, I found your site while researching "danger of ventless gas heaters." My current landlord told me there was a gas fireplace in the apartment before I moved in. What he didn't tell me is it is ventless model, and that it is the only source of heat, save for another ventless gas heater installed in an upstairs bedroom (which has a manual that clearly states not to install it in a bedroom). Good grief! I posted the URL of your Vent-Free Letters Page to the building's yahoo group, where past postings revealed that every winter tenants had complained about the smell. My landlord and his wife saw my posting, and showed up soon after with electric radiant oil heaters, telling us not to use the vent-frees. I'm so glad I found your site and the links you shared.

Jen in Texas


#125: Can I Vent my Vent-Free?
Date: Tuesday, December 28, 2010

How do I vent a vent-free system? Obviously not thrilled with the system, but don't want to spend the money to remove it.

I have a Temco ADL 36-2 that stinks up the house and we can't use it because we get headaches, etc. I simply want to vent the system and be done with it. It is on an exterior wall, so I have to think it is possible.


Sweepy Hi Eric,
A quick scan of
Temco's website didn't find mention of an outside vent option for the ADL 36-2, but you might want to contact the manufacturer to be sure.


#126: Fireman's Fiance Wants To Use Vent-Free: Should He Wear His Air Pack?
Date: Wednesday, December 29, 2010

We bought a house that has a 32,000 btu vent-free propane fireplace in the basement. There is no other source of heat in our basement other than the fireplace (the rest of the house is electric baseboard). I am not a fan of anything gas powered other than my car, but my fiance wants to get the propane tanks filled and start using the fireplace. This situation is ready to send me over the edge... so I wanted to get your opinion on the matter (since you seem to be very smart and run a great website). My fears with a ventless propane burning fireplace center around the fact that it is burning something combustible, and the results get vented back into the room. I have been a firefighter for 17 years, and know for a fact that when something burns there are byproducts created (or else I wouldn't need to wear an air pack to go into a fire). Will this fireplace also create harmful byproducts from the combustion of propane? It is a newer fireplace and was professionally installed so it has the O2 sensor and everything... I just worry that we will be breathing in crap that we shouldn't. What do you think? Are vent-frees safe or should we put in electric baseboard heat like I want to??

David Fritz

Sweepy Hi David,
Your fears are not groundless: no matter what you burn, poisonous by-products are produced. Your oxygen depletion sensor, if it works properly, should shut your fireplace down before you keel over dead, but a growing number of scientists and medical professionals are concerned about repeated exposure to
below-lethal levels. On top of that, propane exhaust contains lots of other goodies like carbon monoxide and nitrogen dioxide. Have a look at the letters on this page, and follow the links at the bottom before you decide to start using the vent-free.


#127: Sooting in Rental Cabin: Typical?
Date: Tuesday, January 25, 2011

We purchased a cabin six years ago and it has ventless fireplace logs in the main room. It is often rented and now our housekeeper tells us that there is black soot on the carpet of the loft, located above the fireplace, and that she has also found black soot on the upstairs bathroom fixtures. We have noticed extensive blackening of the chimney rocks located just above the fireplace opening, but this is the first time experiencing soot on the carpets. Has this really been an ongoing problem for folks with ventless fireplaces?

Kenneth Washio

Sweepy Hi Kenneth,
Sooting is actually one of the most common complaints we get from vent-free fireplace owners. You can read several such complaints in the letters above (check out the photos accompanying letters
#67 and #70).

You-Didn't-Ask-But Department: As you read about the headache, nausea, breathing problem and nosebleed issues in the letters above, you might want to reconsider the advisability of exposing your renters to the exhaust from your vent-free logs.


#128: Plaque or please
Date: Tuesday, November 13, 2012

We have vent-less logs in our brick fireplace and an infrared vent-less stove in another part of our home. Home built in 1954, brick, block and plaster walls with high ceilings. Mold on the inside of the outer walls is a problem anyway just from no insulation. I run dehumidifiers to help. We are looking at closing off our fireplace and putting in a propane heater on the hearth. I have read that the plaque type heaters heat the moisture in the room and infrared heats the objects and that plaque type are a better buy for an older home. Will I still have the same problems from an unvented heater as I do with the logs (smelling, burning eyes etc)? We are looking at the newer models that are propane and natural gas all in one, what is your advice on these heaters. Your expertise would be greatly appreciated. Thank you.

Robbie Steele
La Fayette, Ga.

Sweepy Hi Robbie,
You asked for our advice, so here you go: don't try to heat your house with vent-free gas products, no matter which type. Aside from the immediate problems you're experiencing now (like bad odors and burning eyes), you will eventually face the effects of long-term exposure to gas exhaust.


#129: Vent-Free Gas Logs Gone:  Dizzyness, Drowsiness, Confusion Gone Too.
Date: Monday, September 23, 201

My husband and I moved from Florida to Tennessee and had an Empire VENT-FREE gas log set installed in our new home on 3/19/2010. That December, we began putting the fireplace to occasional use.  The smell from the logs was terrible, but the installers had told us repeatedly to expect an odor, so we dismissed this.

We used this log set, limited to only a few hours at a time, for 28 days  Within a week, with little use of the logs, all our beautiful house plants were dead.  Shortly thereafter, I noticed my husband was having trouble speaking his words correctly.  I, who am never sick, had  gotten to the point I could hardly stay awake for more than six hours at a time, except when we left the house.  On rising from bed I would be so dizzy, I could not stand without leaning onto the wall.  I kept thinking something is very wrong, but by then could not reason well enough to stop using the gas logs.

I am so glad I found your web pages about vent-frees.  Even after being so sick, my husband did not fully accept the problem was the vent-free logs till I showed him your site. 

January 14 was last day of use, and we both immediately started to feel some better. When we contacted the person who sold us the log set and told him we were being made sick by the vent-free gas logs, he danced all around the matter, saying he had never heard of this problem, and he has sold these for 25 years.  BUT he sent someone to our home to remove the logs, and refunded part of our money, enough said.  There is no doubt in my mind that if we had not stopped using that log set, we would have both been killed.

Thank you for your time and effort to make this info available to us.



#130: Extreme medical problems attributed to Vent-Free exhaust exposure.
Date: Tuesday, October 22, 201

My name is Ronald Bouthillier. In 2007 my wife and I  had a home built for us in Florida. We told the builder we wanted a gas fireplace in the family room, as shown in the model home we looked at. I explained that the fireplace had to be vented because I had COPD. At that time we lived in another state, but would travel to Florida occasionally to see how things were progressing.  During one visit we noticed that the fireplace the contractor installed was not vented. We pointed that out to the builder and were told that because we had cathedral ceilings and large windows and sliding glass doors it should not be a problem.

In January 2007 we were ready to move in: all that remained to be done was for the gas company to hook up the gas to the fireplace. The gas tech made a comment that there was little difference in the flame when turned on high or low, but did not seem concerned and said everything was working fine.

After living in the house a little over a year my wife and I both felt very tired all the time, and kept getting headaches while watching TV in the same room with the fireplace.  Eventually, I began to lose my voice and started coughing up blood. Went to see and ENT/Surgeon and he diagnosed me with throat cancer. After 35 rounds of radiation, it looked like I was cancer free. This was in 2008

During the next couple of years we used the fireplace very occasionally, and for only a few hours at a time because the odor from it was overwhelming and we kept getting headaches. Meanwhile I had been going to my ENT and radiologist regularly to be sure the cancer had not come back. As recently as December, 2009 my tests and examinations showed everything was fine.

The winter of 2010 was exceptionally cold, and we used the fireplace more regularly. Due to my COPD I sleep with an oxygen concentrator, and we noticed that the carpeting in the vicinity of its air intake had turned dark gray. I called the company who supplied my equipment and they took it away to check it out, leaving a replacement concentrator and new mask.  The smokey smell in my mask persisted, and when my wife cleaned the machine, the water was black. Only then did I begin to suspect that the problem was airborne soot from the fireplace, which I had been breathing in directly from the concentrator while I slept.

During this time my wife complained that the ceilings and walls were looking dingy. On closer examination we both noticed that the ceiling was showing shadows of studs and nails and corners were very gray, especially in the fireplace room. She called a painter to get an estimate to have the walls repainted and he asked if we had a fire in the house because it looked like there was soot on the ceilings and walls. He noticed our fireplace and asked if we were having a problem with it because he had run into sooting issues before. He chemically cleaned an area of the ceiling and we could see the stark difference between the cleaned section and the rest. He suggested we contact our insurance company as all the walls and ceilings in the house would have to be chemically sponged to get the soot off and then repainted.

Meanwhile I had been coughing up blood again and had to be taken to the ER because I could not breath and I had a rapid heartbeat. At the ER they found I had an irregular heartbeat, raging at 160 beats per minute. I spent about a week in ICU while the doctors tried to stabilize my heart with medication and, eventually, surgery. I had never had a heart problem like this and it does not run in my family. When I finally got out of the hospital I had an appointment with Dr. Brown, my ENT/Surgeon. Upon examining me he found that the throat cancer was "back with a vengeance", and immediately put me in the hospital and performed a laryngectomy (removal of my voice box) and a tracheotomy so I could breath. I remained in the hospital for 3 months. I will have to breath through the trach for the rest of my life, and must to use an electrical device to speak.

This all happened over the course of 3 years' exposure to the exhaust from the unvented fireplace.

The insurance company came to inspect our home, and after all was said and done agreed that the whole house had to be redone. The walls and ceilings had to be cleaned and repainted, all the rugs, curtains, windows and blinds had to be replaced because the soot had stained them. The forced air ventilation system had to be cleaned because the ducting was coated with the soot it had been carrying throughout the whole house. The total bill? $32,000 and never being able to speak normally again.

So if anyone says that non-vented fireplaces are safe let them read this and know what the consequences are. I will never have a normal life. I need to use oxygen all the time. I can’t walk across the street without getting out of breath. If anyone who reads this has any information or knows of any research being done on health effects of unvented gas fireplaces please let me know.

By the way, the insurance company gladly paid to have a new VENTED fireplace installed.

Ronald Bouthillier


#131: Moisture, Mold & Misery
Date: Thursday, December 19, 201

I recently purchased a vent free infrared natural gas heater. After only two weeks of fairly steady use we had to stop using it due to high moisture levels in or house. We now have black mold growing in one of our bedrooms. We had to run a portable dehumidifier for three days to get moisture levels under control. The heater now sits unused. I would not recommend buying vent free products.

Keith Merrill


#132: Low CO Detector Readings, yet Headaches, Confusion Continue.
Date: Tuesday, January 7, 2014

I bought a home about 15 months ago with a ventless propane fireplace. We used it last winter to help heat our home. I began having signs of CO poisoning such as irritability, confusion and severe headaches. I purchased a plug in CO detector alarm and have heard nothing from it. Last winter I eventually gave up on the propane fireplace, still believing it was causing the problems. My wife and I decided to give it another try this last fall. This time I bought a CO meter that reads down to zero ppm and up to who knows. I cranked on the ventless propane fireplace and have gotten nothing much as far as readings go on the meter.... sometimes one or two ppm. I took the meter to my shop where I burn wood and held it over some smoke coming out of the door..... and it zoomed way up quickly.... so I presume the meter is calibrated fairly accurately and is working properly. Since we were believing the tests, we decided to use the ventless furnace again, this second winter. I am getting bad headaches, feel confused, and am unreasonably irritable. I think it must be the furnace, but am baffled about my low or nonexistent readings on my CO meter. My wife, is skeptical about the furnace being the source. Am I just getting crankier in my old age. I just don't feel right or feel like myself... my mental status is degraded during prolonged us of this furnace. Help me understand what is going on.

Logan Swanson, Jasper, Arkansas

Sweepy Hi Logan,
Your confusion stems from the fact that you're chasing the wrong bad guy. Although vent-free fireplaces produce some CO (carbon monoxide), the big criminal is CO
2 (carbon dioxide), which your CO detector can't detect. To sniff out the real cause of your symptoms, invest in a CO2 detector, or an indoor air quality meter with the ability to sense CO2. Google CO2meter to view some options.


#133: Logan Responds
Date: Saturday, January 11, 2014

As you suggested, I purchased a home air quality sensor found on Google.  After setting it up outdoors where the CO2 was reading about 260 PPM, I brought it inside where it very quickly went into an alarm and then an error mode when the PPM display rose above it's 10,000 PPM maximum.  I have no idea how high the CO2 was, but it was up there.  Thanks for steering me onto the right path.  The propane fireplace is off (even the pilot light) now.  I will look into replacing it with a vented one.



To read about how much CO2 a vent-free fireplace exhausts into the breathing space, click here.

To read about a recent study of the effects of long-term exposure to CO gases, click here.

To read about respiratory irritation from vent-free exhaust in the breathing space, click here.

To read a posting about vent-free gas appliances from an indoor air quality scientist, click here.

To read exerpts from a recent Consumer Reports article about vent-free fireplaces, click here.

To read letters in defense of vent-free products, click here.

To read our opinion about vent-free gas appliances, click here.

Have a vent-free experience you'd like to share with the Consumer Product Safety Commission? Click Here.



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