OATEY 39221 2" – 3" 160 DFU Sure-Vent AAV 2" x 3" Sch. 40 ABS adapter

No. The 39221 is for use as a secondary vent only, so the building still needs its primary vent open to atmosphere. Use it on island sinks, remodels, and branch fixtures where running a new vent through the roof is not practical, and leave the main stack in place.

It complies with ASSE Standard 1050 and 1051, which are the AAV standards an inspector will ask about. Local code still governs whether air admittance valves are accepted in your jurisdiction and how high above the fixture trap arm the valve has to sit.

The Sure-Vent valve opens only when the plumbing system pulls negative pressure from a draining fixture, admitting air to break the vacuum, then closes under static or positive pressure. Because it seals shut when no air is needed, it does not vent sewer gas back into the space. It must be installed vertically and left accessible and ventilated to the room.

Its 160 DFU rating covers a substantial fixture load, well beyond a single bathroom group's drainage fixture units, so one valve typically handles a branch serving multiple fixtures. Size the connection to the branch it serves: 2 inch or 3 inch ABS with the included adapter, up to 4 inch vent pipe.

Order it as Oatey 39221, UPC 038753392219. It ships as a single unit weighing 0.5 lb.