wheres that smell coming from?

Bobbo wrote:

westend wrote:

Bobbo wrote:

westend wrote:
Actually, a functioning air admittance valve may allow the trap water to be drawn out quicker when dumping as it allows for the displacement of the trap water.

I respectfully disagree. The one and only purpose of the AAV is to allow air into the drain line, without letting the air and smell back out, to prevent the suction that would pull the water out of the trap. The AAV doesn't accelerate the water draw, it prevents it.

You may disagree but physics is what it is. Think about this for a second. Take a piece of pipe and submerge it in water until there is water in the pipe. Place your hand over the end and withdraw the pipe. Now remove your hand. The water that was trapped in the pipe will then come out the bottom. Your AAV acts just like your hand in this example. If it is functioning, it allows air into the drain pipe when the water is flowing down the drain and closes at normal atmospheric pressure to block any air from coming back out.

Thank you, you just made my point for me. The AAV allows air into the drain pipe downstream from the trap which breaks the suction that would have pulled the water out of the trap. Remember, the AAV is downstream from the trap, not upstream. It would not be useful upstream from the trap because the sink's drain is there and is its own vent.

What you are describing is the way the AAV allows the water to drain out of the drain pipe. I am talking about that action LEAVING the water in the trap via the air the AAV introduces into the drain pipe.

To the OP: The test above about filling the traps with water stopping the smell works. It points to a bad AAV. I have used it.

I assume that my traps had water in them when I dumped. I could see where it might get sloshed around enough in transit to displace any water in the trap thus causing order to seep back in the unit.

So If I run the faucets enough to fill all the traps. Proceed to dump and I still get an odor, this means what?