DuraVent FasNSeal W2 Stepped Increaser: a short step up where a tapered fitting won’t fit
The DuraVent FasNSeal W2 Stepped Increaser is a short double wall fitting that connects a smaller vent pipe to a larger one. It increases the run by one size at a single step, taking the place of a tapered increaser when space is tight. 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. It serves natural gas or propane appliances that call for a special gas vent, including unit heaters and tankless water heaters.
Choose a 4 to 5 inch or 8 to 9 inch fitting on this page. Other size combinations are made to order. Before ordering, check that the size change fits the vent layout specified by your appliance maker. The appliance maker also sets how far the vent may run and which directions it may take. Need the single wall fitting? See the DuraVent FasNSeal Stepped Increaser single wall fitting. The DuraVent FasNSeal W2 Stepped Increaser ships free from My Cozy Outdoors with No Sales Tax (except WY) and the full manufacturer warranty.








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