A pre-fab double wall vertical vent for a gas furnace is commonly known as which vent type?

A pre-fab double wall vertical vent for a gas furnace is commonly known as which vent type?

• A. B-vent
• B. Direct vent
• C. Power vent
• D. Type L vent

Answer: (A)

Gas furnace venting relies on the appliance design to determine the venting method. A pre-fab double-wall vertical vent is the B-vent configuration. It uses an inner exhaust pipe with an outer jacket and is installed to vent upward naturally, relying on the buoyancy of hot combustion gases rather than a fan. This setup is typical for standard, non-sealed-m combustion furnaces and is mounted vertically, often through the roof. In contrast, direct vent and power vent systems use sealed combustion with outside air and/or a fan to move the exhaust, and Type L vent is a different listed vent used for other appliance types. So the described vent matches the B-vent style.

Gas furnace venting relies on the appliance design to determine the venting method. A pre-fab double-wall vertical vent is the B-vent configuration. It uses an inner exhaust pipe with an outer jacket and is installed to vent upward naturally, relying on the buoyancy of hot combustion gases rather than a fan. This setup is typical for standard, non-sealed-m combustion furnaces and is mounted vertically, often through the roof. In contrast, direct vent and power vent systems use sealed combustion with outside air and/or a fan to move the exhaust, and Type L vent is a different listed vent used for other appliance types. So the described vent matches the B-vent style.