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Drain line height too high?

Posted by Whit461 (My Page) on
Wed, Apr 3, 13 at 21:53

Counter installers ran very late. New sink is installed, but it is a very large sink and sits 3+" lower than old sink. As a result the line coming out from the disposal is lower than the drain line connecting through the back wall. To make the connections the line will have at least one more 90 elbow and water will have to push up to drain.

Is this going to work? I can't get inside the wall and under the house to rerun the main drain line.

Follow-Up Postings:

RE: Drain line height too high?

The drain line coming out of the disposal must be higher than any component between it and the wall connection. Otherwise, you will always have drain water in the bottom of the disposal.
How does your 'plumber' propose to 'push' the water up to drain?
Also, that P-trap is installed backwards.

RE: Drain line height too high?

"Is this going to work?"


Water does not flow uphill.

The GD will have standing water and stink to high heaven with rotting waste (and rust out very quickly).

Get a real plumber to open the wall and lower the drain.

RE: Drain line height too high?

Redid whole disposal and drain line over the weekend. Works great, quiet as hell. Had to use an inline vent, but thanks for advice.

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