Dec 5, 2016 · An AAV ONLY allows air in, and if there is a positive pressure, which it can do nothing to eliminate, the drains will not function. Nope - just tested it as per Reach4's …

Nov 13, 2020 · FWIW, It seems as if the AAV are very effective at sealing under pressure, which is what the tests I just made using the tips above seemed to indicate, but the function I really …

Apr 16, 2018 · AAV's are prohibited in the Uniform Plumbing Code, It is not that the UPC specifically prohibits AAV's. It is a default position that AAV's are not an approved product …

Apr 5, 2012 · The AAV is a one way valve letting air in to prevent siphonage, which BOTH traps need and your AAV will provide. The positive pressure situation occurs if the discharge is …

Feb 4, 2013 · An AAV only lets air in. With it in that location, when you flushed the toilet, there's a pressure wave in front of the wave as the stuff flows down the pipe. That would want to push …

Nov 20, 2022 · The bathroom downsteam will be vented temporarily with an aav, and then when renovations are continued next year on the upstairs bathroom, venting will be tied into the …

Jun 25, 2010 · Hey All, My local inspector allowed me to use AAVs on my kitchen double sink, as there was no good way to hard vent it. He said that a double wye with an AAV off the top was …

Apr 13, 2025 · Discussion on installing an air admittance valve (AAV) under a kitchen sink with an S-trap, addressing code compliance and practical considerations.

Mar 18, 2024 · DIY plumbing a basement bathroom in Michigan (IPC) and am wondering about venting. Only real access to existing stack is a 3" line that carries waste from other bathrooms …

Jan 24, 2025 · Yes for the IPC, although that requires you to get the exact slope of 1/4" per foot. Slope it more, you reduce the maximum horizontal. No for the UPC, as it further imposes a …