P-Trap Placement

[JJF]

Trying to pin down the source of a sink odor. I have a bathroom sink that is on the adjoining wall to a kitchen sink. There is a house vent stack that I believe was utilized in a re-plumb for the drains. The kitchen sink and bathroom sink share the drain pipe that is in the bathroom. I noticed that the p-traps for both sinks are higher than the outlet pipe and that in one drawing I came across on the internet it said the the trap seal depth needs to be at least 1 1/2" below the low point of the exit pipe.

So I am thinking of lowering the p-traps to see if that gets rid of the odors. Any other ideas, other than ensuring that this is connected to the vent stack? The crawls space is pathetically small and I need to encourage my 6'4" body to go under there. LOL.

 

[Reach4]

That is bad. In the kitchen, lowering the trap is not going to help. You have no vent as far as I can tell.

In the bathroom, it is possible that there is a vented sanitary tee in the wall, but I seriously doubt it. What it looks like you could do in the bathroom is to add a tee, with an AAV sticking up, where that darker section of pipe is.

 

[Sponsor]

 

[JJF]

Thanks for your reply. Is it feasible to use a Studor Vent Trap on either or both? That would seem to be the easiest thing to implement.

Not sure if I'd need two vents as they both go to the same exit pipe.

 

[Reach4]

Thanks for your reply. Is it feasible to use a Studor Vent Trap on either or both? That would seem to be the easiest thing to implement.

Not sure if I'd need two vents as they both go to the same exit pipe.

A Studor Vent is an AAV. It admits air to prevent siphoning of the water out of the P trap.

Not sure if I'd need two vents as they both go to the same exit pipe.

Kitchen and bathroom would each would need its own AAV. What do you mean that they both go to the same exit pipe? One goes down through the floor and one goes into the wall. If you mean that the drainage merges at a different place, wouldn't that be true for all of your drainage for the house?

 

[JJF]

It seems that the easiest solution is the Studor Vent Trap, as I would not have to cut out the pipes in the back to put a T on it. Anyone have experiences with the Studor Vent Trap?

 

[Gary Swart]

Studor is the brand name of the first AAV. Your problem is obvious. A P trap must be vented before the drain turns down. Ideally, the vent would be in the wall and be unseen. Your drain turns down and is clearly not vented. An AAV will admit air, but there must be a traditional vent in the system. Your problem can be fixed with an AAV teed into the drain line following the trap and before it turns down. It should be as high as possible under the sink. There must be access for replacement since these are mechanical devices and can fail, although this is not occur often.

 

[JJF]

Any opinion on the Studor combo vent/trap? That would be way easier swap-out compared to cutting out the mess in there and adding in a AAV.

 

[Terry]

Any opinion on the Studor combo vent/trap? That would be way easier swap-out compared to cutting out the mess in there and adding in a AAV.

If you can find one. That would be the easy fix.

 

[JJF]

Thanks for all of the replies. I will hunt for a vent-trap!

 

[Gary Swart]

I had never heard of the Studor Trap-Vent until now. I knew about Studor Vents, but these are different. They are designed for sinks that do not have appliances connected. In other words, dishwasher, clothes washer. No reasons give, but I assume it is these would be pumping under pressure.

 

[JJF]

Yes, the Studor trap-vent is new to me as well but am thankful to have found it. Yes, they probably cannot handle the pump pressure that a lot of the appliances have today. Had to replace a busted clothes washer and had to increase the size of the exit pipe as the new machine was pumping out a really high volume of water which overwhelmed the pipe.