I have a dual kitchen sink. One side has water in it the other is empty. When I go to drain the sink, water comes out of the fittings under the sink. The drain line is PVC with the nut type fittings. When I try to drain the water, water goes into the empty side of the sink and water comes out around the nut fitting underneath. I have taken apart the trap system, and it looks clear. I used the Roto Rooter drain cleaner overnight. I tried to drain the sink this morning and it still did the same thing.
You have two different problems here:
1. Your joints are leaking. Could be that they are not tight enough, not aligned straight to each other, compression rings not in place in the right direction or encrusted with dirt and debris to keep from making a good seal. The lightweight pvc drains are generally easy to work with but are also easy to cross-thread. Once that happens, the joint will leak. Easiest fix here is to spend the $10 to get all new drain parts and replace.
2. The rush of drain water from one side is pushing up on the other sink drain. There *should* be a 'T' between the two that has a build-in baffle that keeps this from happening. If the wrong combination of parts were used to make the cross drain, where there is no baffle to restrict the cross-flow then you will have your problem. Here too, it may be best to just get a new double sink drain kit and start over.
Thanks Jaybee. I was thinking that is what I would probably have to do, but just making sure. I will try that. Thanks again.
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