View Single Post
Old 09-15-2022, 09:46 AM   #7
Carl n Susan
Site Team
 
Carl n Susan's Avatar
 
Join Date: Oct 2005
Location: Carmichael - CA
Posts: 7,323
M.O.C. #4831
That is an Air Admittance Valve that is used in place of a vent stack.

https://www.oatey.com/faqs-blog-vide...ittance-valves
__________________
Carl (n Susan)
There is more to life than fuel mileage.
2012 Montana 3700RL Big Sky Package towed by a 2015 Ford F350 6.7L PSD 4WD CC LWB

Carl n Susan is offline   Reply With Quote