Forum Discussion

zach477's avatar
zach477
Explorer
Nov 27, 2015

Replaced air admittance valve, Still stinks.

Today I replaced the air admittance valves under the kitchen and bathroom sinks. I was getting oder under the sinks while driving.

After I took a shower, I noticed the same smell from under the kitchen sink, but not the bathroom sink. This was my last shower before going to the dump site tomorrow. The grey tank has been "full" for a day or two, but no water was coming up in the shower so I figurd I'd be fine.

Even with a full grey tank, the AAV shoukd still be doing its job, right? What gives?
Class A

16 Replies

Show More
  • zach477's avatar
    zach477
    Explorer
    Nov 28, 2015
    rseymour21 wrote:
    Dumping your tanks might also solve your problem.



    I'm almost positive that it will, however, I'd still like to know how/why the smell is getting in.

    Even with empty tanks, I there is an foul smell that creeps in while driving. I'd like to know where it's coming from.
  • zach477's avatar
    zach477
    Explorer
    Nov 28, 2015
    I just used the cheap black one. I'll try switching them. I'll also try some rubber conditioner on the flapper.

    I tried testing them before I put them on by blowing into them like a tuba mouth piece, and all seemed well. Now that they've had that gross gas going though them I probably won't do it again...
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Nov 28, 2015
    John&Joey wrote:
    zach477 wrote:
    Even with a full grey tank, the AAV shoukd still be doing its job, right? What gives?


    I have a 5'ver that when the tanks become filled there is an overflow pipe. Prior to it hitting the ground, it sits on top of the tank (I think.) Don't smell so good.


    Waste tanks do not have overflows.......EPA Hazard :B

    But the drain pipe and vent pipe going into top could be installed using a grommet vs being hard glued.
    With an overfull tank the grommet can leak



    OP.......
    Did you use one of the inexpensive (cheap) AAVs ? $3-$5
    That just have a flapper pulled close by a rubber tang



    Studor makes a better one and more expensive $20+
  • John_Joey's avatar
    John_Joey
    Explorer
    Nov 28, 2015
    zach477 wrote:
    Even with a full grey tank, the AAV shoukd still be doing its job, right? What gives?


    I have a 5'ver that when the tanks become filled there is an overflow pipe. Prior to it hitting the ground, it sits on top of the tank (I think.) Don't smell so good.
  • gbopp's avatar
    gbopp
    Explorer
    Nov 28, 2015
    If you replaced two valves and it stopped the odor at one location, possibly the new valve at the second location is bad.

    Just because it's new doesn't always mean it's good.
    The valves are built from plastic and rubber.

    They're not precision built like a Swiss watch. :)

    Try switching the valves, if the odor location changes you will know one valve is bad.

About Motorhome Group

38,738 PostsLatest Activity: Jul 25, 2025