DuraVent FasNSeal W2 Eccentric Increaser: a wider horizontal vent without a low spot
The DuraVent FasNSeal W2 Eccentric Increaser is a double wall stainless steel fitting that connects a smaller vent pipe to a larger one. Its larger opening sits off center. That lets a horizontal run widen without creating a low spot where condensate, the liquid formed as exhaust cools, can collect. It also shifts the center of the run to help it pass an obstruction. 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.
This fitting connects an 8 inch pipe to a 10 inch pipe. A gasket seals each connection, and a locking band built into the wider end holds the joint together. Each joint takes up 2 inches of pipe length, which matters when planning the run. W2 pipe cannot be cut to fit on site. An adjustable length handles the remaining gap instead. Need the single wall fitting? See the DuraVent FasNSeal Eccentric Increaser single wall fitting. The DuraVent FasNSeal W2 Eccentric Increaser ships free from My Cozy Outdoors with No Sales Tax (except WY) and the full manufacturer warranty.








Commercial projects may require custom parts and unique system designs. Duravent offers complete project assistance:








































