Need advice on sewer smell/gurgling from kitchen sink, have spent over $1,000!

[barefoot14]

We've been in our home, which has radiant heat concrete floors, since 2001. Last year our triple bin kitchen sink started getting clogged up a lot. We finally had a plumber out who replumbed the entire thing ($334). Then we started hearing a lot of loud gurgling in the far right sink when we were washing dishes in the far left sink and sink backing up again. Heavy sewer smell emits from same far right sink. Called plumber, he cable cleared the drain in our slab from triple compartment sink to main drain, ($304), then it was draining good. No resolution to gurgling and sewer smell. Plumber came out and replumbed again ($410), this time removing the garbage disposal unit. But we still have the loud gurgling and sewer smell. Now the plumber is talking about doing something else which would cost several more hundred dollars! What should we do????

 

[Matt30]

Is the drainage going into the wall 2" or 1 1/2"?

If it's 2", that sink can be plumbed with one 2" trap instead of two 1 1/2" traps. You may be getting siphoning action causing your smell

 

[Zanne]

Hmm.. Looks like there's an AAV (Air Admittance Valve) instead of an actual plumbing vent. Could that be part of the problem?

I think it would be simpler if there was a single trap. I'm wondering about the slope of those pipes as well. It's hard to tell from the pictures. I could be wrong, but just eyeballing it, it doesn't look to me as if it slopes downward when coming from the trap from the righthand sink.

Do you think it would work to put something like a sanitary cross in the middle, have the drain come straight down from the middle sink and the left and right slope down to merge with it, then have a trap and go into the wall (possibly with the AAV on there just before it goes into the wall)?

(I'm not an expert so I'm hoping some experts can weigh in). It also looks to me as if the AAV is only serving the far right basin.

Also, depending on the size of your garbage disposal, you might be able to put it back in its outlet isn't too low to have it slope downward to the cross and then still have a downward slope (1/4" per foot) to the wall. It's possible the opening to enter the pipes in the wall might have to be moved lower, but I can't tell.

Awesome sink, by the way.

Also, not sure if this is helpful or not since there are no pictures: http://www.ehow.com/how_5840230_plumb-compartment-sink.html

 

[Matt30]

That AAV isn't doing much of anything. It may as well be capped off placed like that.

 

[Zanne]

Yeah, I don't know much about the AAV's since they are not even allowed in my state. I just noticed that only one of the drains is attached to it. I think I'd want my money back from that plumber.

Also, you could probably re-plumb the thing yourself (if you're allowed to do so in your area) instead of having the plumber come back. It looks simple enough and the experts here could walk you through it. They helped me with replumbing my kitchen sink.

 

[frodo]

mat is correct, http://screencast.com/t/rspOXrJJM

looks like 2''. exactly whats happening, one trap is sucking the other dry

you can do it your self for 20 bucks worth of fittings

 

[phishfood]

That AAV isn't doing much of anything. It may as well be capped off placed like that.

With a lot of respect to my brother from the great white frozen north, I have to disagree.

The location of that AAV will allow it to do everything that it is capable of. All an AAV can do is to allow air into the piping. Either trap that is draining will pull air through the AAV before it pulls air through the other trap.

The first thing that I would try is to replace the AAV, in case it is sticking closed. But my best guess is that you have a partial clog in the drain line, causing a positive pressure situation in the piping underneath the sink when you drain the sink. The right hand trap is getting "blown out", causing the gurgling and the sewer smell.

 

[Zanne]

Maybe they could still re-rig it the way Frodo sketched it and pop a new AAV on it after the trap? They could have adapters to make it go from 1 1/2" to 2" and have a 2" sanitary cross, then a 2" trap and so forth.

Does that sound like a good idea?

 

[barefoot14]

Thanks to everyone for the advice, so far. I am going to wait and see if more ideas come in, then present them to my plumber, who I hope will see this as a challenge and not continue adding to the costs...this has become quite a STINK, er I mean SINK. ;-( Hope this post doesn't show up twice, I had a technical difficulty with the site...

 

[frodo]

pop outside, look on the roof is there a pipe sticking up close to that window?

if so, you do not need that auto vent, what you need is one trap, not 2

 

[Zanne]

pop outside, look on the roof is there a pipe sticking up close to that window?

if so, you do not need that auto vent, what you need is one trap, not 2

I was wondering about whether or not it tied in to an existing vent, but I noticed that a vent pipe in that wall might not be able to get 6" above the flood level of the fixture before it would need to go horizontal. So maybe it was removed or never put in. Ideally they would have a vent pipe going out the roof though.

 

[Caduceus]

I've peeked into this thread a few times since its introduction and feel that for the benefit of the original poster I need to add my feelings on the subject. Let's take a look back to the beginning.
The OP has lived in the home for 12 years before the initial complaint.
The first description of the symptoms would indicate that there is a clog.
After augering, the drains flowed normally.
The gurgling and odor returned shortly after even though a repipe was done, which would tell us that the repipe did not contribute the relieving the problem and may not have been necessary in the first place. Were back to square one with the issue.
The drains probably need a very thorough cleaning/clearing and there is a possibility that the pipe could be damaged underground. A camera inspection (mini-cam, maybe) to confirm after the pipes are properly cleared.
That's where solving the problem should start. Repiping, AAVs, 2" traps and all that are secondary or tertiary until then.
On that note, all fixture drains should have their own trap. Each trap should have a vent. Not sure about the details of your codes, but connecting double or triple compartments together before one trap is a no-no. You now made one clogged trap affect two drains (one of the basins is now considered safe-wasted into the other).
Anyways, I wasn't there so this is just all speculation; The plumber first arrived and cleared the drain and everything was eezy-peezy lemon-sqweezy, or so he thought. So he upsold the job into a repipe and figured it probably needed it and he'd never be back again anyways. Turns out, the pipes needed a little more TLC after the traps and when returning to the same call, he had to do something and now options are limited. So some other stuff is done and some suggestions are made and the customer is going to keep paying for the whole 'process of elimination' diagnostic routine....which, by the way, is sometimes necessary, but I don't believe in this case it is.
This just brings us back to the beginning again. Gurgling and a foul odor.
You could call another plumber, but the first plumber would then be under no obligation to service or warrant anything that was done by him if another plumber services the same sink. You could instead rent a sewer snake for the drain size, try to clear it out yourself and follow up by using a chemical treatment to remove any missed debris. You would be responsible for any problems, damages, costs or liabilities, but you are now more in tune with what's going on and may feel comfortable with that. You also don't have to tell the plumber if you worked on it yourself, but he might be able to tell if he's experienced enough, though doubtful.
Finally, if it were a "What would you do?" situation and I wasn't a plumber I would call the plumber/company back and say "I paid $XXX.XX to solve a problem and the problem is still there. Apparently what was done was unnecessary. I expect the problem to be solved at no additional cost."
Do not mention social media or lawyers because they may then have the right to refuse future service even if they are wrong.
Hope some of this info is useful. It's my day off and I'll now have a Corona with my sushi for lunch...a great combo. You should try it.

 

[Zanne]

Correct me if I'm wrong, but if the sink basins are all 30" or less apart on center, they can all use the same trap, right?

 

[Caduceus]

No, Zanne. Plumbing codes that specify traps per drain is interpreted incorrectly a lot of times. Especially by design, inspection and consultation firms like in the example given in your post. A kitchen sink may be considered a single fixture with a single faucet, but can have one, two or three fixture drains. Each fixture drain should have it's own trap. The firm that you got that diagram from has quite the resume, but proves once again that most general contractors and consultants are not qualified to do what they propose they can do for the public, for a fee. There are exceptions for safe-wasted appliances or appurtenances, but that doesn't apply here.

 

[Zanne]

No, Zanne. Plumbing codes that specify traps per drain is interpreted incorrectly a lot of times. Especially by design, inspection and consultation firms like in the example given in your post. A kitchen sink may be considered a single fixture with a single faucet, but can have one, two or three fixture drains. Each fixture drain should have it's own trap. The firm that you got that diagram from has quite the resume, but proves once again that most general contractors and consultants are not qualified to do what they propose they can do for the public, for a fee. There are exceptions for safe-wasted appliances or appurtenances, but that doesn't apply here.

Ahh. Ok. That is good to know. So, do you have a diagram of what would be the best way to plumb it? I'm guessing 3 different entry points into the wall?