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Sweepy Direct Vent Gas Appliance Installations


The Problem:
Any time there is a fire in a gas stove or fireplace, a significant amount of oxygen is consumed by the flames. This causes negative air pressure in the house, which can draw cold air in through other openings. In worst cases, this depressurization can drag poisonous exhaust gases back down the chimney into the breathing space.

The Solution: Bring in combustion air through the same pipe used to vent the exhaust. In Direct Vent installations, combustion air is drawn into a sealed firebox from outside the house through coaxial intake/ exhaust pipe. This eliminates depressurization, resulting in a warmer, healthier home environment. Direct venting also eliminates the need to extend the exhaust vent through the roof, making installation easier and less expensive.

Note: Direct venting only works for specially designed GAS appliances. Wood fireplaces and stoves must exhaust into a vertical chimney extending through the roof. To read more, click here.


How Direct Vent Pipe Works:

Sweepy Unlike older gas stoves and fireplaces that required a vertical vent pipe or chimney through the roof, Direct Vent models can simply be vented out an adjacent outside wall. Most direct vent appliances, however, need some vertical rise in the vent pipe for proper operation. Typically, a 24" vertical length is required before the pipe turns and penetrates the wall, but some stoves are listed with shorter rises or no rise at all. For example, the Hearthstone Tucson is listed with a 9" vertical length instead of a 24" length: the Hearthstone Sterling HT vents straight out the back, and may be installed with no vertical pipe at all.

Even stoves that require a vertical rise can be installed without any visible pipe inside the house using a Snorkel Cap, which creates a 24" rise outside the wall.

Examples of Direct Venting Techniques:

1: Direct Vent Installations
Through an Outside Wall

1) 24" Vertical Length
1) 90 Degree Elbow
1) 11"-14" Adjustable Length
1) Wall Thimble Collar
1) Horizontal Vent Cap

This popular configuration is
available as a prepackaged kit

2: Snorkel Vent Installations
Through an Outside Wall

1) 11"-14" Adjustable Length
1) Wall Thimble Collar
1) Snorkel Vent Cap

The Snorkel Cap creates the rise
on the outside of the wall, so no
vent pipe is visible inside the house

 

 

3: Basement Installations
Through an Outside Wall

To clear windblown debris and snow drifts, the bottom edge of the vent cap must be 24" above grade. If the top of the soil is low enough on the wall, a snorkel cap can be used to accomplish this.

If the top of the soil is too high to enable use of a snorkel cap, vertical lengths can be added to the inside vertical pipe, to raise the bottom of the standard cap 24" above grade.

Note: 2" clearance must be maintained between the horizontal pipe and the ceiling

 
 

 

 

4: Vertical Venting
Through The Roof

If the stove is located on an inside wall, or if above the roof venting is desired for any other reason, Direct Vent stoves and fireplaces can also be vented vertically, using the same type of roof flashing and storm collar typically used for wood stove chimneys.

A vertical coaxial cap is substituted for the horizontal cap used in thru-wall installations.

Note: most Direct Vent appliance listings limit the height of vertical venting to 30 -35 feet.

 

 

5: Venting Into Unused
Manufactured Chimneys

Manufactured chimney coaxial conversion kits are available for most common double-wall and triple-wall manufactured chimney sizes. Round fittings are attached to the top and bottom of the chimney, and connected by a length of 4" aluminum flex liner. The chimney cavity around the liner is used to deliver combustion air to the fire.

Coaxial Direct Vent Pipe is used to connect the stove to the bottom fitting

 

 

6: . Venting Into Unused
Masonry Chimneys

Masonry chimney coaxial conversion kits consist of fittings for the chimney top and thimble hole, connected by a length of 4" flexible aluminum liner. The liner carries the exhaust, while the flue cavity around the liner acts as the combustion air intake passageway.

Coaxial Direct Vent Pipe is used to connect the stove to the thimble fitting.

 

 

 

7: Venting Into Fireplace Chimneys
Using a Co-Linear Direct Vent System

When a Direct Vent stove is installed standing inside or in front of an existing fireplace, we can't use the masonry conversion kit shown in diagram #5 above because we don't want incoming combustion air to flow into the room through the fireplace opening. For fireplace installations, a Co-linear intake/exhaust system is used. A co-linear converter box at the bottom of the chimney is connected to a similar box at the top by two lengths of 3" aluminum flex, one for intake and one for exhaust. A coaxial rain cap completes the installation. With this system, combustion air is contained within the intake flex so it can't enter the room through the fireplace opening.

Note: The 3" aluminum liners are small enough to snake right through the fireplace damper opening, and flexible enough to allow the bottom converter box to be oriented sideways for rear-vent stoves.

NOTE: OUR DIRECT VENT GAS APPLIANCES COME WITH DETAILED, STEP BY STEP INSTRUCTIONS FOR DO-IT-YOURSELF INSTALLATIONS. TO VALIDATE YOUR WARRANTY AND ENSURE OPTIMUM SAFETY AND PERFORMANCE, HOWEVER, FINAL SETUP ADJUSTMENTS AND INITIAL FIRING MUST BE ACCOMPLISHED BY A TRAINED GAS SERVICE TECHNICIAN. CONSULT YOUR GAS SUPPLY COMPANY FOR A LIST OF RECOMMENDED SERVICE TECHNICIANS IN YOUR AREA.

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