AAV under kitchen sink

Does anyone write up air admittance valves in plumbing.

I had one today in a mobile home and wrote that they can fail and if the smell of sewer gas is present it should be replaced.

They are common in mobile/manufactured homes. They are a mechanical device, subject to failure over time. Many jurisdictions allow them.

Perhaps better would be that if a sewage smell is present, recommend further evaluation by a licensed plumbing professional. It might be something other than the AAV, so the AAV might not need to be replaced. Let the licensed plumber make that determination. But the warning to your Clients will help keep you out of trouble with unwarranted callbacks.

Here’s a couple good sites on AAV’s.

](http://www.toolbase.org/TechInventory/techDetails.aspx?ContentDetailID=851)

](http://www.studor.com/index2.htm)

Thanks for the help, I don’t see them to often but I do know they can fail and will change my wording in my reports.