Air Admittance valves

[Skeetzee]

2014 Flagstaff Microlite 21-FBRS. Wondering how long Air Admittance valves on the sinks generally last? I changed mine out a few years ago from the cheap stock valves. But having trouble with smells..wondering if there is something wrong with them, or one of them, again. Google says they should last for 20 years! thanks!

[Kimber45]

I dont know how the work or what would break on them but i read threads about them all the time. Google is probably right most the time.

[Skeetzee]

I understand how they work. Just don't know life expectancy in a travel trailer. What would make the seal fail?