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DBecker
Dishwasher Drain Plumbing

I an remodeling a kitchen and installing an under-mount sink. The sink is deeper and being under-mounted, the drain connection is now lower. I do not have a dishwasher, so the current dishwasher connection is a dishwasher drain fitting between the sink drain and the p-trap, in that vertical pipe run. With the new deeper sink, this fitting (about 3-4" long) will have to be removed. I may be able to install it under the side sink (which is not quite as deep), or in the horizontal drain coming from it. My concern is that the water may back up in the other sink. The only other option may be to tear out the wall and try to lower the drain connection for my p-trap. Can you give me some guidance here?

Thanks,
Dan

johnjh2o
Re: Dishwasher Drain Plumbing

If it's a double sink you can put the dishwasher tee in the line between the two sinks but it must be before the trap.

DBecker
Re: Dishwasher Drain Plumbing
johnjh2o wrote:

If it's a double sink you can put the dishwasher tee in the line between the two sinks but it must be before the trap.

John,

Thanks for the reply. I was hoping that I could put the dishwasher tee in between the two sinks like you state. This pipe does shoot straight into the tee connection where up is out into the main sink, and down is to the p-trap. This is not a y-type connection. Do I need a different connection there to prevent water from coming up to the sink?

I got in a hurry in my first post and said I didn't have a dishwasher, but meant disposal.

Thanks,
Dan

Mastercarpentry
Re: Dishwasher Drain Plumbing

Probably not if the drain works as well as it should. The DW drain pump doesn't have a lot of flow or pressure involved so I think you'll be fine. IIRC, they also make a fitting with a built-in directional diverter to aim the flow away toward the drain side, but these also introduce a restriction for the sink drains so use them only when you have to.

Phil

DBecker
Re: Dishwasher Drain Plumbing
Mastercarpentry wrote:

Probably not if the drain works as well as it should. The DW drain pump doesn't have a lot of flow or pressure involved so I think you'll be fine. IIRC, they also make a fitting with a built-in directional diverter to aim the flow away toward the drain side, but these also introduce a restriction for the sink drains so use them only when you have to.

Phil

Thanks guys. I think this part of my job will be a lot easier than I thought it might have been.

Dan

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