View Full Version : Stink under sink/ AAV Valve

11-22-2004, 11:07 AM
Hello all, I'm new to the forum so please be kind.

Anyway, we have been in our newly built house for six months and we've noticed (been overwhelmed by, is a better phrase) a stench (I think sewage) under our kitchen sink which happens to be an island sink. The dishwasher is to the left. There is a single pvc pipe jutting upward from beneath the floor and at the top is what I believe to be an AAV vent (Sure-Vent is the brand, I think.) The drain pipe for the sink attaches horizontally to this pipe about 8 inches or so below the top where the AAV vent is. There is a p-trap in the sink drain pipe and there is no stink coming from the sink drains themselves, only from the cabinet space under the sinks. I've tried to detect if there is a similar stench coming from the dishwasher, I don't think there is although sometimes it seems like I can smell a little - could be because I'm so close to the the sinks. I have been advised by other amatures such as myself, that this vent may be for pressure relief when the water is shut off. This doesn't make sense to me since the sink drain pipe is attached. I also believe that this pipe attaches to a large drain pipe (about 5 inches) under the house. All my investigation leads me to believe that, since this is an island sink, a regular vent which usually runs all the way to the roof could not be installed so this AAV Vent was used.

Also, the dishwasher drainage flex pipe is attached to the sink drain pipe. The only thing I need to ensure, is whether or not the dishwasher drain pipe is attached on the sink side of the p-trap and not on the other side.

I am guessing that this AAV Vent is malfunctioning, perhaps stuck open allowing sewage gasses into the house.

Any ideas? Am I on the right track. I just want to make sure that the plumber who installed and is probably at my house right now, has all the info he needs.


11-23-2004, 05:39 PM

I am so prejudiced against the AAV's and the problems they cause users that it is wise you asked responders to be kind. We normally install an island vent for island sinks. This configuration consists of a pipe that comes up through the floor to the top of the sink counter top and then back under the floor where it runs under neath the floor to a wall where it then turns up and vents to the outside.

This smell is unfortunate in a six month old home. I'm curious if this is how the plans called for this sink to be vented and if you are located where your home was permitted and inspected. If you are not on a slab, have you checked the crawl space for leaks? I get the impression you are on a slab. I presume the installng plumber has been there by now. Was he able to cure the odor problem?

11-30-2004, 08:55 AM
Thanks for the response. Yes the plumber came out and replaced the AAV with a different brand. He said it was the first time he had used that particular brand/type. Anyway, the smell is gone and I hope this one will last.

11-30-2004, 09:29 AM
It would probably be wise to keep a spare AAV around. Terry must have added the picture of the island vent explanation I was trying to describe. Thank you Terry.