Smell coming from bathtub with AAV

[Lestle12]

My cabin was built last year and since they finished every now and then it smells like sewage. It’s coming from the bathroom tub upstairs. The tub, sink, and toilet have run to a single Oatey vent I can access through a closet. The valve is rated at 24/160 dfu.

The smell only is coming from the tub drain. Also when this is happening and you flush the toilet you can hear it flush in the tub. My builder has replaced the valve several times. The cabin does have 1 stack.

Any advice please??

 

[Terry]

I would guess that the rough plumbing is at fault. Do you have pictures of the plumbing before the drywall went up?

 

[Sponsor]

 

[hj]

Either your tub does not have a trap, or the seal has dried out. that is why you can hear the toilet flushing and smell the odor. Run some water in the tub to reseal the trap, if you have one.

 

[Terry]

Either your tub does not have a trap, or the seal has dried out. that is why you can hear the toilet flushing and smell the odor. Run some water in the tub to reseal the trap, if you have one.

Darn it, I forgot to mention water to be run in the tub first. When I go to peoples home and walk by their big deck tubs in the master bathroom, I always run a bit of water for them to refill the tub trap. Most of the time I see plants in pots, or clothes racks sitting in the tubs.

 

[Lestle12]

Here's some pics of the plumbing. It does have a small p-trap on the tub. If I run water in the tub that makes it better. However if I flush the toilet and let it refill flush it again, and so on i'll start to hear it again in the tub and the smell will come back.

 

[Lestle12]

tub from under

 

[Terry]

Normally you would vent the tub before it enters the line with the toilet. The toilet might be siphoning the tub trap.

Below on the 3/4 drawing, the lav wet vents the tub/shower and then it goes to the 3" with the toilet.