DuraVent FasNSeal W2 Tapered Increaser: a gradual change to a larger vent size
The DuraVent FasNSeal W2 Tapered Increaser is a cone shaped double wall fitting that joins a smaller vent section to a larger one. Its taper gives the exhaust a gradual path into the wider pipe instead of an abrupt step. FasNSeal W2 is DuraVent’s double wall stainless steel vent for high efficiency gas boilers, furnaces, and water heaters, with an air space between its two walls. On this page, choose a 3 to 4 inch or 3 to 6 inch transition to match the two vent sections it will join.
W2 can sit as little as 1 inch from wood and other materials that can burn, depending on the appliance’s exhaust temperature and whether the run is exposed or enclosed. It also serves outdoor runs below the roof line that would otherwise need an enclosure. Keep support sizing in mind when ordering: W2 uses the single wall line’s support clamp and wall bracket, sized 1 inch larger than the vent. Need the single wall fitting? See the DuraVent FasNSeal Tapered Increaser single wall fitting. The DuraVent FasNSeal W2 Tapered Increaser ships free from My Cozy Outdoors with No Sales Tax (except WY) and the full manufacturer warranty.








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