Double sink stink

[Mark Garrenton]

First, I d like to offer my condolences to the family for their loss. It’s never easy. Never.

We had a double sink installed in our bathroom addition. Both sinks had their own J trap and drains into the wall plumbing. The left sink started to stink of septic gases within a few months. I plumbed the sinks together with individual J traps and a tee into just one wall drain while blocking off the other inlet at the wall. The stench subsided briefly but came back. I then plumbed the sinks together with a tee and only one J trap at the wall drain. The stink still exist at the same sink on the left. I don’t know what to do at this point. How else can I address this disgusting problem?

 

[Jeff H Young]

probebly plumbed wrong. are the drains clear ? somehow one of the traps loses the seal? unvented ? maybe an aav . A good drawing and or photos could help

 

[Sponsor]

 

[Tuttles Revenge]

A P-Trap prevents sewer gases from coming from the sewer into your living space. Unless they're installed improperly. There should be water in the U bend under the J bend. If there is water there, then likely the smell is coming from another source than sewer gases. The likely other culprit would be some form of gunk growing in the overflow tube and or the drain portion of the overflow tube.

 

[Jeff H Young]

could be over flows only after a few monthes ? Seems fast to have happen. there are ways to clean it out with bleach or other product

 

[Tuttles Revenge]

could be over flows only after a few monthes ? Seems fast to have happen. there are ways to clean it out with bleach or other product

Seems there have been a lot of similar issues posted here that seem to track back to overflows. But I could imagine a trap with no proper vent installed that is siphoning.. Tho honestly I think that is unlikely. I've seen lots of improperly installed traps that never seem to siphon.

 

[Tuttles Revenge]

I wonder if this is what the trap under the sink looks like? Seems like a stretch, but possible.

 

[Donn2390]

I'm having the same issue. Recent guest bath remodel, including new vanity and new Toto sink, along with new P trap and pluming from sink to wall. Everything appears correct, P trap installed properly, etc. There was never an odor prior to this work being done. The odor was present from first day, close the drain and no odor. I pulled the P trap and see if somehow water is syphoning off but it was full of water. I'm out of ideas...

 

[Jeff H Young]

rescent guest bath remodel can mean differant things . assuming only a sink change and p trap its baffling . so what about pipes behind the walls and fixture locations nothing changed ?

 

[Donn2390]

The builder fiberglass tub/shower combo was replaced with a tile walk-in shower, new vanity, sink, faucet, new shut off valves, hot and cold, new drain and all drain piping to the wall, including new P trap.
I did a lot of testing including placing rubber sheet over shower drain to make sure it wasn't coming from there. I can shut the sink drain and leave it closed over night and the smell doesn't exist. Open drain plug and it returns.
I can try cleaning pipe back into the wall, but the P trap should stop any odor from there.. I can keep the drain closed, but that doesn't work when expecting guests..
I appreciate your help..

 

[Jeff H Young]

only way for stink to come through the trap is if the seal is broke which means water level dropped

 

[Reach4]

I can shut the sink drain and leave it closed over night and the smell doesn't exist. Open drain plug and it returns.
I can try cleaning pipe back into the wall, but the P trap should stop any odor from there.. I can keep the drain closed, but that doesn't work when expecting guests..
I appreciate your help..

How about a photo that shows the lavatory trap, the connection at the wall, and the lavatory drain (tailpiece)? That photo might show why your trap is ineffective.

Also, there could be stuff growing, in the passages, that stinks. Consider killing that off with bleach, and maybe something that makes the bleach more active. But careful. Too much of that something can release chlorine gas, so great care needs to be used to not get the pH too low (acid).

Start by closing the stopper, and lightly dripping water into the bowl such that water slowly dribbles into the overflow. I would start with maybe 1/2 cup of bleach and no activator. So how could smell from stuff growing in the passages be blocked by the sink drain? Maybe closing the drain blocks air flow, so the smell does not waft up.

Also, maybe the photo will show that this trap could be cleaned or replaced.

To eliminate concern that the problem is venting, dribble maybe a cup of water down the drain, but do not close the plug. The slow flow cannot trigger siphoning of the trap. Still got the smell?

 

[Donn2390]

Good ideas, I will take some pictures when I get home. In the mean time I will start with a cup of bleach and let it sit in the drain for a few hours and see if that does anything..

 

[Jeff H Young]

yea maybe its just got a lot of old nastyness in the drainage run a small snake down if you have one I use vinegar and or baking soda just because I have it on hand down traps once in a while

 

[Donn2390]

Don't know why I didn't think of vinegar as I have a cup sitting in my emptied and dry toilet right this minute, to get rid of some of the stubborn stains on the very bottom.... Figure it should be clean as a whistle by the time I return.

 

[Breplum]

Don't know why I didn't think of vinegar as I have a cup sitting in my emptied and dry toilet right this minute, to get rid of some of the stubborn stains on the very bottom.... Figure it should be clean as a whistle by the time I return.

I've never had great luck with vinegar (and did use muraitic acid over the years), but pretty darn pleased with EdFred Cling'n'clean Toilet bowl Cleaner.

 

[Jeff H Young]

I

I've never had great luck with vinegar (and did use muraitic acid over the years), but pretty darn pleased with EdFred Cling'n'clean Toilet bowl Cleaner.

I was just talking about what I use for regular or semi regular minor cleanning I dont generaly put chemicals in my drains. ill put baking soda and vinegar it foams up but its not super powerful like muriatic

 

[Reach4]

Muriatic generates really nasty vapor on its own, as it comes from the bottle.

Chlorine bleach with a strong acid makes really nasty vapor. When you reduce pH to make chlorine bleach more active, keep the pH higher than 5.0. To me, that means measuring the pH before adding the bleach.