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pcampbell 11-06-2008 01:59 PM

Kitchen drain pipe after P-trap goes UP??
It goes through the P-trap, then has a big upward angle, then straightens out. Even when it is straight, I just stuck a level on there, and it's on an upward incline. Is this acceptable? To me I would not think it is but I really do not know how this all works. Our kitchen drain is not draining and I am wondering if this has to do with it. It has been in place for a while and working OK but it seems very strange . My understanding was that water should naturally "fall" (1/4" per foot or something?) toward the end of the drain after the P trap. I don't know if this is part of our problem but I also do not know if it is helping or hurting.

MikeVila 11-06-2008 02:44 PM

Sounds like you found the problem. Especially when you say a "big" upward angle. I believe it is 1/4" per foot also.

pcampbell 11-06-2008 02:50 PM

IT goes through the P-trap, then it goes up more maybe another 4", then it goes straight, but the straight is not straight, it's up. That is a very slight angle, albeit up.

Thishas been working for, 6 months, and of course I never noticed it until it stopped draining. I do not think that this is the ENTIRE problem, since it was working previously.

I guess what I am trying to figure out if this issue is just making it worse, or is it somehow the cause (i.e. if something has been building up for months because of this issue)...

I have been running a 1/4" 25' auger through, and it just does not seem to be doing much. I want to try a larger auger, and longer, before doing anything drastic... We may need to cut a hole in the back of our kitchen cabinet in order to fix this drain pipe???? :censored:

DUDE! 11-06-2008 04:04 PM

a plumber most likely can explain this better but I don't believe it should be pitched up. before cutting into the wall, check to see if the pipe slipped. I don't know if its metal or plastic, but they loosen up and slip sometimes. Ideally it should come off the trap and the tail peice goes right into the wall. Could be because of crowded space they did it different. Someone before you might of added to the drain and made it a longer run to the trap.

JDC 11-08-2008 12:01 AM

No, no, no, no! It DEFINITELY shouldnt be pitching upward. That's called backfall and that IS your problem. The drain should be pitched at 1/4" per foot to the stack or branch. In addition, you stated that after your trap the drain goes up 4"????? Who scabbed this nightmare together? Yeah it "worked" for 6 months, but it really WASNT working properly thus leading to your clog. The water wasnt draining, but was being pushed through the pipe due to head pressure from the sink. Anytime your sink wasnt running that water that is laden with grease, soap, food particles, etc etc etc was sitting there in the pipe...not draining. All that gunk and gook (those are technical plumbing terms:laughing:) starting clinging to the inside of the pipe walls and VOILA you have a clog.

Yes, you need to get into the wall and fix this. Without seeing it and going only on how you've described things, I'd guess that you need to get to the stack, lower the tee then rerun the fixture arm over. After that's finished, find the person who created this monstrosity and tell him/her that he/she owes you a 12 pack of your favorite adult beverage.:whistling2:

Good luck

buletbob 11-08-2008 06:07 AM

is this constructed out of PVC. And if so Did the trap slide down from the sink tail piece to give it this back pitch. I have seen this happen twice when These stainless steel dish washers came about. because of the hotter water temps created, thous bending the pipe. just a suggestion! BOB

tribe_fan 11-08-2008 08:19 AM

I agree with Bob - you should first investigate if the piece from the sink to the P trap is too long or slipped, before having to go into the wall.

You said it was working for 6 months - did someone add a disposal or new sink ? A picture would help.

jadrma 11-08-2008 01:00 PM

sink drain alignment
I discovered a similar problem. I noticed water leaking from my p-trap connection located between the sink drain and the beginning of the p-trap. This was odd since it was dripping long after the faucet was off. I looked and saw that the horizontal run from the p-trap to the wasteline was actually higher than the p-trap and waste line from the garbage disposal. This means there is standing water in all of those lines since the T into the main waste line is located about 2" below the sink drain and above the p-trap and all the various connections. I plan to cut back into the wall, cut through the main vertical drainpipe, add a T at a lower point, and cap off the old T. One of many DIY projects lying ahead.

pcampbell 11-08-2008 01:11 PM

2 Attachment(s)
To answer the questions. It was working fine, and by that I mean draining perfectly normally, for 6 months before we re-did the kitchen (and installed the disposal) and then for another 6 months after.

I honestly may have put too much crap down the disposal, and did not post-flush it with hot water long enough. Now We are composting 90% of our food so... that should help.

I think that it's possible the p-trap slipped down. The nut on the disposal side just slips on after all. I have to move it up, and see if I can't get it to be at least at a slight downward grade.

I did actually call the roto rooter man, and he said that the configuration was OK but not ideal. The price, FWIW, was $140.

He used his power auger well beyond 25' - and it seemed like once he got the crud into the large 3" or 4" main sewer line, all was well.

Here is a picture - worth 1000 words. Let me know what you think... thanks for all the replies.

jadrma 11-08-2008 01:24 PM

Kitchen drain pipe goes up??
You're right...the picture helps a lot. Logic would tell you that you have a problem. Based on the height of the wasteline going into the wall you will always have water standing in the system no lower than that level. IOW, the complete p-trap AND it's fittings as well as the bottom of the disposal will have standing water in it. As long as those fittings are totally leakproof "underwater" it's not going to cause leakage but it could contribute to clogging. It's similar to the problem I described a couple of posts earlier. The p-trap needs to be lower than the final run into the wasteline but that final run should be lower than the various fittings leading to the P-trap itself.

pcampbell 11-08-2008 01:34 PM

It sounds like if I just didn't have a disposal I'd be fine and it would simplify things ;)

It's funny because my wife didn't want one, I just had to have it... doh!

Termite 11-08-2008 03:44 PM

Someone really screwed that up, didn't they! The rough-in at the wall was brought out at the wrong height.

DUDE! 11-08-2008 05:12 PM

Pcamp, I really think that once one of the plumbers on here takes a look at the setup you have, he/she will be able to advise how to correct the problem. With space at a premium under the sink, not much room to work with.

buletbob 11-08-2008 06:26 PM

It looks as tho some one changed there mind on putting in a disposal after the plumbing was rouged. :eek::eek: :laughing::laughing:
It looks like your going to be working on your stomach for awhile. Could you run the drain through the floor and pick up the waste line as it comes out the floor bay? in the basement then cap the old waste and cover the back of the cabinet with some birch ply. BOB

tribe_fan 11-08-2008 07:19 PM

Unless the clog is in the short piece, then the source of the problem is the disposal. If your House is old the pipes are probably 1/2 clogged until it gets to the 4 inch pipe. ( I replaced one once and could not believe how restricted it was) Old houses and new disposals just don't mix. ( I'm not saying that the pipe shouldn't go down hill, but with a dishwasher I would think it would get flushed regularly.)

You might be able to use the disposal I you have someone thoroughly snake the line to wherever it goes to 4 inch, or change the pipe if you have access.

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