This is what the kitchen sink drain looks like in a house I recently purchased. Let's see if we can count how many things are incorrectly done.







I'll go first.

(1) No air gap or at least a high loop from the outlet tubing coming from the dishwasher.

(2) Dishwasher outlet connected to the drain AFTER the p-trap allowing sewer gas from entering the DW, plus the positive pressure from the DW draining can siphon the sink trap.

(3) The disposer side is going through a double trap.

(4) The dishwasher outlet pipe elevation is too high, even higher then the wall stubout.

(5) A straight vent tee is used to union the left and right sink SCH40 piping.

(6) The kitchen faucet has a pull out spray with a hose looped through the cluster of drain plumbing so it cannot be pulled out more than a few inches.

Anything else I missed?



Edited 1 times.

Looks like since everything is solvent welded I need to take everything back to the wall and go from there.

If I use a different more compact model disposer, any chance I can make the outlet elevation of the disposer higher to the point it will work in relation to the current wall stubout elevation? Or must move the sanitary tee inside the wall?

7) the whole flow is incorrect to the drain imo, like, water coming from the left sink at speed is gonna go right past the outlet and go into the right side trap.

8) I believe the electric isn’t right either, unless gfci, those appliances should be on single outlets (so nothing else can be plugged in other than the semi-permanent appliances)


My $0.02 is return the drain design to the original - put a separate trap on each sink, and run them into the left and right ports on that triple fitting in the back. Keep the center one plugged as the cleanout. Connect dishwasher hose into dishwasher inlet port on new disposer. I think you’re right, get one of those small ones and egress pipe is higher.



Edited 1 times.

sum, that drain a way too high for a disposer.
just use two traps and a direct connect DW tailpiece and eliminate the disposer.

Quote

..... Let's see if we can count how many things are incorrectly done. .....

add: you bought the house




==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

That is the ONLY "error" that counts and the only one that cannot be cured by rearranging the piping. I do not know of any "good" disposer that would attach to that wall outlet without being full of water all the time.

Probably best to re-work the plumbing in the wall (if you are wanting to keep disposal option)

Install new trap arm at a more workable height.
On occasion I abandon completely the plumbing in the wall and come out through the floor and cabinet a good location to rebuild drains in the cabinet space. Sometimes AAV. Sometimes re-use vent. My first fitting is a 2" clean-out tee. Next is a 2 x 1 1/2 x 1 1/2 ABS Santee as drain, vent, and trap arm.

For kitchen sink I find 14" AFF works even with deep sink and disposal.
Let that disposal go that you have. Badger 1/2 HP is fine replacement. Should bring disposal 90 up some too.

Interesting plumbing set-up you have now. wow. that was A LOT of work to build that. A for effort.



Edited 1 times.

It WAS a lot of work (wasted time) by someone to do this, most likely since 1992.

I will have to break the wall and lower the sanitary tee to about 12" above finished floor. If I can install a cleanout I will probably put one in at where the drain outlet is now, then below it the new sanitary tee. Assuming the pipe behind the wall is 2", then I will put in a 2" CO, below that a 2" sanitary tee.

Is there such a thing as a 2" tubular p-trap or the largest is 1-1/2"?

I will probably put in a double wye like it is now and a 1.5" trap adapter at each branch so each side has it's own p-trap. If not I will pipe the disposer side straight to the left sink tailpiece with a baffle tee then use it's p-trap. The SW will be hooked up to the disposer side inlet with a high loop.

Sure, there is a 2" trap, what you use for shower drains.

- - - - - - -

Not a plumber by trade but a fierce DIYer

LI GUY, you must be too excited with the yanks pitchers and catchers starting today because you missed the word "tubular" in sum's question.
sum, you never know in the wide, wide world what is made or not made. but i am pretty confident there is no such ting as a 2 inch tubular trap.

Packy in that case if I put in a double 2" wye into the sanitary tee at the wall (kind of like it is now but lower), I can put into each branch of the wye a 2X1.5 trap adapter, and into that the individual p-trap outlet tube. I kind of like the trap adapters because it allows me to take them apart (to clean, swivel, rotate, adjust...) if necessary. Solvent welding the entire p-trap with 2" SCH40 takes away that possibility.

Thanks Packy, I see what you mean!

- - - - - - -

Not a plumber by trade but a fierce DIYer

sum, we can use slip joints on the outlet side of a trap in MA.
so I would use a 2 x 2 x 1 1/2 x 1 1/2 double "Y".
traps into each 1 1/2 opening and a full size 2 inch cleanout in the end of the "Y".