Sometimes installations require You to increase the diameter of a gas appliance's vent. You should always keep some Gas Vent Diameter Increasers when using Dura-Vent Type B piping. Applications - DuraVent Dura-Vent's Type B Gas Vent system is for 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 for a wide range of applications, including: natural gas fireplaces, gasfired 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. Round Type B Gas Vent 10" - 16": Aluminum .016" inner wall, galvanized .021" outer wall. Round Type B Gas Vent 18" - 30": aluminum .020" inner wall, galvanized .021" outer wall. 3"-16" diameters feature twist-lock fittings, screws required for 18" and larger diameters. Clearances - 1" clearance to combustibles in single and multi-family dwellings. Listings - UL Listed to UL 441 and UL 1777 (MH6357). ULC Listed to ULC S605 (CMH1276 & CMH1407).
- Adjusts from 5 Inch to 6 Inch length
- Increases vent diameter
- For use with Dura-Vent Type B Gas Vent pipes
- 4" tall
- 25-year warranty