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Byrogie's avatar
Byrogie
Explorer
Aug 17, 2017

Can I add air admittance valve?

So, our kitchen sink vents on the side of the trailer. And, of course it is right where I like to sit on the deck. If the wind blows just right we get smell. It also sometime goes back through the window by the sink, that gets the wife.
Can I plug that vent and install an air admittance valve under the sink? And, do I put it anywhere between the trap and the stack?

thx

6 Replies

  • Bobbo's avatar
    Bobbo
    Explorer III
    bartlettj wrote:
    It's ok if you have another external vent for the tank it feeds. If you don't, you are asking for trouble. The AAV has a one way valve that only allows suction to replace the air that went down the drain with the water, so if pressure builds up in the tank, it won't vent it. Any tank pressure will bubble through the trap unless you have a rooftop vent.

    Very good point, and important!
  • It's ok if you have another external vent for the tank it feeds. If you don't, you are asking for trouble. The AAV has a one way valve that only allows suction to replace the air that went down the drain with the water, so if pressure builds up in the tank, it won't vent it. Any tank pressure will bubble through the trap unless you have a rooftop vent.
  • Had the same problem with an old 5th wheel. We just added bleach to the sink/tank then dumped. No more odor.
    Dave
  • Byrogie wrote:
    So, our kitchen sink vents on the side of the trailer. And, of course it is right where I like to sit on the deck. If the wind blows just right we get smell. It also sometime goes back through the window by the sink, that gets the wife.
    Can I plug that vent and install an air admittance valve under the sink? And, do I put it anywhere between the trap and the stack?

    thx


    YES.......
    Downstream of 'P' trap on a 'stub pipe'

  • Our camper has one at the kitchen sink from the factory. You should be able to as long as you have the room for it.

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