Water supply stub out behind dishwasher?

[kktalker]

As part of our kitchen renovation, we are rearranging our kitchen island to have, from left to right, a dishwasher, sink, second dishwasher, cabinet, and icemaker. The plumber located the hot and cold supply lines coming out of the slab as shown in the diagram by the red and blue circles, behind the left dishwasher. The sink drain is shown as the yellow circle (to be vented with a Studor), and the ice maker floor drain is shown as the green square. There isn't room for a 2x4 wall behind the island cabinets for plumbing/electrical; it all has to run through cabinets.

Does the location of the hot and cold supply lines behind the dishwasher look problematic? Is it important that I relocate them to come out of the slab below the sink cabinet?

 

[Reach4]

I don't know the answer to your question, but I would point out that dishwashers are usually only hooked up to hot.

 

[Sponsor]

 

[Themp]

You need to ask the plumber how he is going to do the connections to the appliances and sink. There is not much room under a dishwasher, but after the floor is completed, the plumber might be then putting 90 degree fittings on the supply lines and then running those lines down the counter on the floor and branching off for the appliances and sink(I assume your counter/cabinet will have toe space). Would be nice to have shutoffs for everything also, so ask how that is going to be done. You would think that bringing the supply lines up under the sink would be the best, but what are those wires coming out of the pipe about? If that is the electrical supply lines, I have never seen anything like that before. You would think those wires need to be protected and have some kind of color to them for hot/neutral/ground. And having them under the dishwasher is strange also. The plumbing supply lines what are those pipe sizes? They look small. 1/2 inch would be nice.

 

[Plumber69]

How old are those water lines? You may want to run new ones if they are fairly old

 

[MACPLUMB]

you need a NEW plumber !
the correct way would be to bring them up under the center and the split off to the two dishwashers the same with the drain
ideally would be to bring them up in the center and bring two separate hot water pipes one at each dishwasher as while as a cold one at the icemaker location

 

[Highlander]

Sometimes dishwashers don’t leave a lot of free space behind (and are the pipes popping up right at the back of the planned cabinet cavity). You’d want the shutoffs for dw and icemaker accessible so under the sink, much easier if the supply lines pop up in that cabinet space. Can’t quite see but do you have enough electrical for the 3 big appliances plus whatever general purpose countertop outlet? I wonder how he’s venting the floor drain.

 

[Storm rider]

You might ask about your wiring installation in the electrical forum, but I think most places don't allow romex to run in conduit. I think it has to be derated if you do that.

 

[kktalker]

Thanks everybody. The polite version of the story is that the plumber who started this work was not chosen by me, was not instructed by me, and will not be continuing the work (same for the electrician). So I can't go back and ask him what the heck he was thinking. I need to decide what I want before I bring in someone else to bid the job. I'll take any tips on how to get someone else to come in to take over the work. Is no one going to want to touch this? Do you think I'll need to sign a waiver on warranty of work?

Before the renovation, there were two islands (hence the two slab holes). The island where the water supply stubs now had a secondary sink that then fed water to the primary sink in the other island (where the icemaker drain is). Highlander, the icemaker floor drain uses the vent in the wall from the previous primary sink.

I think I want the supplies moved to come up through the sink cabinet floor, branching hot for the two dishwashers and cold for the icemaker, but the the icemaker line still has to run behind the right dishwasher. I could run water to the icemaker up through the slab, but with that floor drain, there is not any room left for it to come up.

Themp: the water supply lines are 1/2".

Themp, Highlander, and Stormrider: Thanks for the tip-off about the electrical. The wiring comes up within the sink cabinet about 2" from the left back corner. It's four runs of NM-B 12/2 in that conduit. Everything you see in the pictures has passed rough plumbing and rough electrical inspections, but I live in an area where inspectors seem to be pretty lax, and I care more about doing it right than passing inspection.

 

[Storm rider]

The conduit runs under the ground, which makes it, by definition, a wet location. NM-B is not rated for a wet location. It may have passed inspection, but I wouldn't do it in my house. It will be a lot easier to pull new wires now than it will be after the cabinets are in and an underground short knocks out all the power in your island.

 

[Chefwong]

You only have like 3 feet of concrete....in the middle. I would hammer it out, dig and redo the feeds entirely. Since you can deal with this now since you're at the bones of the shell I would have hot/cold on the kitchen and second cabinet with Dual Shutoff T's on both sides. Either a dual shutoff or T off the feed with single shutoffs on each ends. Gives you option on whether to hook the DW to hot or cold. For a china/crystal setting, one DW can be cold water and the other hot. For the valves that are not in use, just put a 3/8 cap as a extra safety net.

KKtalker. Do you entertain alot ? aka, the need for 2 DW. They make a 25 minute cycle DW - take a 240V but it's ah-mazing

 

[kktalker]

Chefwong, no, we don't entertain much. But we have a large family and scratch-cook three meals a day because of medical needs. Yeah, when the first of several people suggested designing for two dishwashers, I thought it was pretty hoity-toity, but oh man, I get it now.

 

[Chefwong]

You won't regret it. Not sure what DW you have now, but MOST modern dishwashers take 2 1/2hrs . Some cycles take 3 1/2 hrs.
The one I mentioned in my reply takes 25 minutes.
There is also a newer one that will do medium/light soiled loads in 51 minutes...

For sure double DW is always a advantage .....