DuraVent Model BV Increaser: a step up to a larger vent pipe
The DuraVent Model BV Increaser is a fitting that joins a smaller gas vent pipe to a larger one. It lets the pipe grow by one or two sizes at any point along the run. Most often, it sits just above the draft hood connector, where the appliance exhaust enters the vent. That is useful when the appliance outlet is smaller than the vent size called for by the fuel gas code tables. Model BV is DuraVent’s Type B gas vent, the double wall pipe that carries the exhaust from a gas furnace, boiler, or water heater out of the house.
Choose your size change: 3 to 4 inch, 3 to 5 inch, 4 to 5 inch, 4 to 6 inch, or 5 to 6 inch. Other size changes are available by special order. Vent sizing follows the fuel gas code tables and appliance manual, not DuraVent’s choice. The vent needs at least 5 feet above the draft hood, and more with a bend or two appliances sharing it. Short on room? See the shorter DuraVent Model BV Low Profile Double Wall Increaser. The DuraVent Model BV Increaser ships free from My Cozy Outdoors with No Sales Tax (except WY) and the full manufacturer warranty.
Details
SKU: 3BVX4 | 3BVX5 | 4BVX5 | 4BVX6 | 5BVX6
Applications
Duravent’s Type B Gas Vent system. Use with natural gas or liquid propane Category I and draft hood equipped appliances, and appliances tested and listed to use Type B Gas Vent. Applications include: natural gas fireplaces, gas-fired furnaces, boilers, water heaters, and wall or space heating applications.
Materials and Construction
Round Type B Gas Vent 3″ – 8″ and Oval 4″ – 6″: Aluminum .012″ inner wall, galvanized .018″ outer wall, in Canada, the lengths have a galvalume .018″ outer wall. The 3″ – 8″ Round gas vent features DuraLock® and DuraTab® . The Oval gas vent features the button lock.
Round Type B Gas Vent 10″ – 18″: Aluminum .014″ inner wall, galvanized .018″ outer wall. DuraLock® feature for 10″ and larger diameters.
Round Type B Gas Vent 20″ – 30″: aluminum .023″ inner wall, galvanized .018″ outer wall. DuraLock® feature for 10″ and larger diameters.
Clearances
Clearances to combustible materials in single and multi-family dwellings:
- 1″ Clearance – USA – 3″ to 30″
- 1″ Clearance – Canada – 3″ to 24″
- 2″ Clearance – Canada – 26″ to 30″
Annular insulating air space
- 3″ – 8″ Round Vent: 1/4″ air space
- 4″ – 6″ Oval Vent: 1/4″ air space
- 10″ – 30″ Round Vent: 1/2″ air space
Diameters
- 3″- 30″ Round Diameter.
- 4″, 5″ and 6″ Oval (USA only)
Listings
UL Listed to UL 441 and CAN/ULC-S605 (MH2848 and MH17667).