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Anything Wrong With Two P-Traps?

Posted by candler (My Page) on
Wed, Nov 3, 10 at 17:17

My washer has a good, regulation height 2-inch P trap. Where it connects to my primary drain line is directly across from where the laundry sink connects. The laundry sink has a 1-1/2" p-trap. When the washer is draining water comes into the laundry sink. I have enough room to put two p-traps between the laundry sink and the primary drain line. Would it help? Thanks.

Follow-Up Postings:

RE: Anything Wrong With Two P-Traps?

The drain line is partially clogged or just smaller than required for the washer.

RE: Anything Wrong With Two P-Traps?

candler do not install two P traps in a series.

If you want to change something, 1st look at the connector where the two incoming drains both face each other. There are several kinds with different names: double fixture fitting, double Wye, double Tee, double San-Tee, Cross, Baffle, and so on. Your fitting may be the wrong one. Before drawing any conclusion, post a photo of this fitting.

RE: Anything Wrong With Two P-Traps?

My house is a 1965 vintage. It originally had all cast iron drains but now sort of a mix with pvc. The primary kitchen drain line comes through the basement where the washer/laundry sink are It is 2"ID. The connecting washer drain and laundry sink drain is also 2" ID. You're right about the primary one being too small but that'll never change.

I don't know how to post a picture to THS and the fitting's location is pretty much blocked anyway. I went to the Home Depot site to see plumbing fittings. The cast iron primary drain line fitting that I'm talking about looks like an SxSxSxS cross.

A little of the washer drain water coming into the laundry sink has always been an irritant but that's as far as it went. Now I've bought a few used kitchen cabinets and a regular kitchen sink to put there. That changes things. My neighbor said to look at a T-valve. I'll check that out. Thanks.

RE: Anything Wrong With Two P-Traps?

Double trapping is prohibited by the plumbing code.

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