[jheald1]

The Problem:

I just moved into a new house, and while doing the dishes, noticed that the kitchen sink backs up after running water for about 30 seconds. The sink does drain, but it is painfully slow. I thought it was a clog, so I tried Drain-O, and a pipe snake. Neither of those fixed the problem, so I disassembled the p-trap (on the double sink) and ended up replacing it.

An Observation:

Before closing on the house, I asked the seller to replace a leaky vertical drain pipe (thick PVC, maybe ABS) in the basement. I have a sneaking suspicion that the horizontal drain pipe (from the kitchen sink) ties into the vertical drain pipe in the basement. I think that when the vertical drain pipe was replaced, the new pipe was a fraction of an inch longer, which pushed the horizontal drain pipe off level. I think the kitchen sink backs up because the horizontal drain pipe slants towards the sink, not the vertical drain pipe, creating a back up.

The Question:

Can I simply remove a 1/2 inch section from the vertical drain pipe, in order to create the proper slant in the horizontal drain pipe, and correct the flow of water?

[siberianair]

Drain pipes should be a little off level for the water to flow. Of course it should be a downhill battle not uphill...

[jheald1]

I understand that the horizontal drain pipe should not be level; the end connected to the vertical drain pipe should be lower than the end connected to the p-trap.

My problem, as I explained in the last sentence of my "Observation", is that the horizontal drain pipe is tilted so that water flow towards the sink, not away from it.

I have looked into clogs, both in the p-trap, and in the vertical drain, yet nothing I've done has solved my problem. I still need to know if I can reduce the length of the PVC vertical drain pipe in the basement.

[creahands]

If u can see horizontal drain from sink. Put level on it. Should have 1/4'' pitch to vertical pipe.

Are u talking about the stub out thru the wall to P trap?

Cutting the vertical pipe will only work if the horizontal pipe is free standing. If going through wall, may not have clearance for movement.

Chuck

[iamgrowler]

Cutting the vertical pipe will only work if the horizontal pipe is free standing. If going through wall, may not have clearance for movement.

Not only that, but the horizontal run, depending on which way the floor joists are run, may be drilled through floor joists or fire blocking and be locked in, which would inhibit the ability to pull the pipe up.

If this is an ongoing problem, I'd bite the bullet and open up whatever is necessary to expose the horizontal run and correct the problem as you see it, not as you imagine it.