Confused by this kitchen sink backup!

[Ken in MN]

Hey everyone; new user to the site and was hoping someone may have some ideas for us!

My wife and I just moved into a home that was built in 1987 that is connected to city water and sewer, but in the past had well and septic. We had a renovation done in our kitchen that put new granite with double sinks and a new disposal (there was no disposal before). Everything worked fine for about a week. On thanksgiving, both of the sinks wouldn't drain and backed up. I took apart everything underneath the sink and checked the traps and the pipes. There was no blockages. I put everything back together, strangely enough everything worked again. We ran the dishwasher with no problems etc. Then, the next morning it happened again while my wife was doing dishes. I removed everything again and ran a 15' snake down the pipe that the sinks connect to. Nothing blocked. Now it's still backed up. Also, the disposal has a dripping leak from the bottom of the housing. I also heard some sort of alarm which sounded like it was in the pipes somewhere when I tried sink this morning.

The two sinks drain into one 1.5" pipe that is by itself. The 1.5" pipe runs through the basement rafters and connects to the main line which is exited into the sewer. There are no other problems with any other sinks / drains / toilets etc. I'm about to start beating my head against the wall on this problem. Any help or suggestions would be GREATLY appreciated!!

[mtcummins]

post pictures of your undersink plumbing and any other lines you can see.

[Ken in MN]

Sorry, I was at work and unable to post pictures on my original thread. In talking with a family friend who's a plumber, the concern he had was with how the pipes are under the sink and not having enough venting? There are 2 traps under the sink.. one near the exit to the main pipe going downstairs and the other underneath the t from the disposal... Does this shed some more light on the issue??

[dlarrivee]

Wow. That is special.

Why are there two traps there?

[cacher_chick]

The first thing I would do is kick the person who installed that mess under the sink. Twice.

[jimbo]

You wont need any sink stoppers to wash dishes! That sink will never drain! Lose the double trap, and fix the outlet from the disposer which seems to slope upwards. Drop the disposer directly into a Tee into trap, figure out how to make all the other connections. When you add it all up, the drain into the wall may be too high, and might have to be lowered.

[Ken in MN]

Thanks for the input everyone; much appreciated it. Our GC is coming back over tomorrow night to take a look at things again. He swears it's a plug in the line going into the main line.. even after I told him that I ran a 20' snake through and there was no blockages what so ever.

We didn't have an undermount sink or granite (or a disposal for that matter) before the remodel. Are we maybe running into an issue with the 9" deep sink and the big disposal on that side??

[mtcummins]

You're running into a problem of a contractor who has no idea what they're doing. Every time I say I think I've seen it all...

Looks to me like the drain line is low enough, if you didn't have 2 traps in there. keep the basic setup you have, but lose the trap nearest the exit, as jimbo said. Check the slope on the cross from the disposer, again as jimbo said, it looks to be running uphill to the tee. if that is the case, you need to lower the tee, which may require a new tailpiece on the right bowl if its not long enough. Then just go off the first trap straight to the wall. make sure everything runs slightly downhill, i think it should line up just about perfect once you lose the 2nd trap.

and don't hire whoever that was again, at least not for plumbing. this is 101 stuff here, not a complicated venting issue or something. no excuse for mistakes like that.

[hj]

With 2 traps in the line it will NEVER drain, or will drain very slowly, at least at first. Whoever did it was NOT a plumber, but you may need a "real" one to get it connected properly. YOUR 20' snake was probably too small to even affect as stoppage, if there were one.

[Ken in MN]

Well the GC's contractor came over last night and hooked it up correctly and everything looks fine. BUT, the sinks still don't drain Our next step is to have drainking come by later this afternoon and check out the pipes to see if there is a plug somewhere.

The GC tried to tell me a "told you so" story after it was hooked up correctly. Until I showed him this forum and a few other resources to shut him up. Hopefully we'll have a working sink later tonight with no major problems along the way.

Thanks again everyone for the help and I've learned a few valuable lessons regarding contractors this week!

[cacher_chick]

I just hope the guy didn't work on any of your other plumbing.

[Gary Swart]

If the GC did the redo, it probably still isn't right. With all due respect to you, you should hire a real plumber to deal with this problem. It really isn't going to be very complicated for a professional, may not even need new parts. Also, while I have no personal knowledge of "Drainking", I suspect it is similar to Roto Rooter or other franchise drain cleaners which often are not a very good choice.

[hj]

The rule of thumb is that ANY company with "Drain" or "Rooter" in the name could be a bad choice.