Helping my brother in law remodel his kitchen and found this under the sink. What was here was a double bowl sink, with disposer on the left side. Both sinks had their own traps and connected into this wye, Was this right? I thought on a double bowl sink you used a horizontal tailpiece to connect both sinks into one trap. The new sink is single bowl, qhat the best way to deal with this wye?


Unrelated question....right after I took this pic, their kid was taking a shower and we got water out of the wye,about 1/2" in a pail. What would cause this?

there are a few options for connecting the new sink.
best way depends on where the outlet for the new sink lands in the existing cabinet.

one thing for sure you need to snake the drain to clear the partial stoppage.

There might also be a problem with the drain pipe installation, if the sink drain is being wet vented by the shower drain pipe.

depends on the centerline of the new sink drain, could probably use one branch as the cleanout and one branch for the new sink p-trap outlet. Or just cut the entire wye off, looks like there is room to cement in a trap adapter such that the nut is still outside of the wall, if not can cement in a drain coupling with a spigot trap adapter.

Is the new sink a deeper sink? If so the garbage disposer may be lower than before.

Thanks guys. Went over there today and was told that a toilet flush upstairs produced water in the bucket at the kitchen sink. Some investigating in the basement and it appears that both full baths upstairs come down into the 3" pipe that the kitchen sink ties into in the wall.
BIL is calling a plumber (licensed, insured, and bonded, they have used him before, bern) tomorrow to get the partial stoppage snaked, will see if the plumber has anything else to say about the situation and will report back.

House was built in 1976 and there is a curious mixture of ABS pipe and PVC fittings, not sure why.

Good point about the deeper sink, hope I don't have to open the wall and lower the drains.

Closing this one out. Brother in Law got a plumber to come and snake the line, apparently there was a partial clog that he cleared. Good call on that one Packy! Once the line was snaked no more water from kitchen drain.

More good news, the new sink was also double bowl and not much deeper than the old one. I was able to reconnect P-traps to the existing wye with just enough vertical clearance to connect the sink and disposer!

Thanks again guys for help on this one!!



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