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View Full Version : Sink drain. Won't.


schwim
Feb 17, 2008, 01:46 PM
Hey there guys,

Getting ready to wrap up a kitchen remodel, and I've run into an issue.

I moved the sink drain stub about 5 feet to the right. The only things I changed when doing the remodel, plumbing-wise was I connected the vent stack that had opened up in-wall and I attached some hangars to the drain pipe in the basement, as it was sagging.

Today, I hooked up all of the plumbing and filled the basin with water to test the drains. I let one fill up and then released the stopper on it, leaving the stopper in the other. It drained for about 5-10 seconds then just... stopped. I waited a few more seconds, then I pulled the stopper on the other side. It filled up the other basin until the two sides were equal in level. Once that had happened, it eventually drained (with air coming from the drains at the beginning of the process, but stopping after the initial belch), but took over 10 minutes to do so.

My initial thought was that the vent stack that I had reconnected was plugged somewhere and since it was raining, I simply added a cheater vent under the cabinet until I could get on the roof to snake the vent stack. See the picture for where I added the vent.

I filled the basins again(this time both, since I was positive that I had solved my problem). I pulled the stopper and the same thing happened. They began to drain, then when slowing, air emitted from the drains, and then eventually just slowing to a crawl while finishing the draining process.

When this happened again, I decided to unthread the cheater vent to see what would happen. I could hear a siphoning sound when I first unthreaded it, and it began draining again, but then the water actually came through the vent's threads and I had to thread it back up. Loosening it caused the water to come through again, so up the vent stack was less resistance than down the drain.

I'm stumped. The pitch seems OK and the sink drained fine before the remodel. I moved the sink to the right 5 feet, reconnected the vent stack in-wall and used hangers on the drain pipe in the basement.

What would my first step be in finding out the problem? It acts like a stopped drain, but I can't see how it would have happened during the time that I moved the sink. I didn't change the direction of the drain, so the drain still has the same relation to the vent, just a little bit further away.

This is the current drain setup under-sink:

Tried a cheater vent.... (http://www.infosprite.com/gallery/main.php?g2_itemId=1070)

Any help would be greatly appreciated, as the problem is driving me batty.

Thanks,
Json

massplumber2008
Feb 17, 2008, 02:05 PM
Hi schwim..

It is not uncommon for old drains to plug up after a remodel... even if you have repiped the upstairs. See, here, waste that is clinging to old pipe sides is used to being moist so when you stop using drain during remodel it just cakes up and dries... usually contracting andfalling off pipe walls... THEN when you add water back down drain the dried waste becomes like a plug and clogs the drain.. so snaking is not a bad idea.

Try that and get back to us. Good luck

schwim
Feb 17, 2008, 03:05 PM
Hi there MassPlumber,

:)

Stumped on what to do, I decided I'd go down and cut the pipe on either side of the first L and see I I could look down either run.

I cut the pipe in two locations(noting that water was pouring out at the first cut!) and pulled it down. This is what I found in it:

The culprit. (http://www.infosprite.com/gallery/main.php?g2_itemId=1074)

I looked down both runs and there was some detrius hanging from the waste lines, but not to the degree of what I found in the cut portion.

I reconnected the line, went upstairs and removed the cheater vent, replacing the threaded cleanout in it's place and filled up the basins.

They clean out in record time :) I really appreciate the suggestion and I'm very happy that I don't have to reformumlate my under-sink plumbing :D

Thanks again,
Json

massplumber2008
Feb 17, 2008, 03:14 PM
Thanks Schwim... glad if I helped... what a mess huh? Take care.