Help me MacGyver a portable dishwasher hookup

Here’s the situation:

I’m renting a house with no dishwasher. Installing an under-the-counter dishwasher is something I don’t want to do and neither does the landlord–would require tearing out cabinets. But I need a dishwasher. (Please, no advice about doing them by hand.)

There is a service porch with a washer/dryer stack. There’s a PVC standpipe to drain the washer, an available outlet, and of course hot and cold water taps with hoses running to the washer. There’s enough space to fit a portable dishwasher in there.


  1. Water in: I can split the hot water with a simple Y fitting, right? Will I want hose threaded or 3/4"?

  2. Attaching to dishwasher hose: I know that for portables you’re meant to attach the water line to the faucet. How do I adapt that fitting to connect to water-splitter?

  3. Draining. I think I can just cut the top of the PVC and add a pipe with two branches–something like the below–right?

3A. Draining part 2: The PVC standpipe is 2 1/2" outside diameter. Is that enough to accommodate the water from a draining clothes washer and dishwasher at the same time, or should I run them separately?

Thanks for all help and will provide more info if that is needed.

I don’t know anything about rigging your plumbing, but did you know there are countertop model dishwashers? They are basically a half-size dishwasher–one rack–and hook up to your sink. Might be an easier solution (assuming you have more than one chunk of counterspace and a small household). :slight_smile: Good luck.

First, I like Elemenopoly’s suggestion. No muss, no fuss.

Second, I am not a plumber. I make no warranties that this will work. To answer your questions:

1.a, Yes, a “Y” fitting will work. A “T” fitting will be easier to find & cheaper as well.

1.b, I would go with a “T” fitting with 2 garden faucets attached. Make sure that they are rated for the heat of the hot water. Use one for the Washing machine & the other for the dish washer. This way you can control them individually.

  1. You can buy a ready made adapter for that purpose. I used one in a cabin I lived in thirty years ago.

  2. Yes. I used a simple “Y” without the additional curve. I suspect that would work better than the one pictured.

3A. Perhaps. I ran them at separate times as the well could not supply enough water to run both of them at the same time.

May I suggest that in any case I would put the dishwasher drain in the top & the washing machines drain into the side. While the washing machine drain puts out a lot more volume than the dish washer, its output is at a lower pressure. It will be less likely to blow itself out of the drain pipe.

I used the dish washer to clean auto parts. Dishes I washed by hand.

Again, I would look hard at the counter top style of dishwasher as Elemenopoly suggested. It will be easier to install & virtually guaranteed to work with little changes to your plumbing. It will also be more likely to be acceptable to the land lord & you can more easily take it with you when you move. Any change to the plumbing that you install to make the portable dish washer work beside the washing machine will be your responsibility. IOW, If it fails, YOU are responsible for any damage. You also could not legally take it with you when you leave.

IHTH, 48.

By the way, the one I linked to doesn’t require any plumbing. It snaps on your faucet when needed like a portable dishwasher.

Anyway, I looked into these a lot a few years back, when I was in the same situation. Ended up getting a full size portable on casters because I had the room for it, but I was told they operate the same. I’m not entirely sure what a “service porch” is, but I’m guessing it doesn’t have a utility sink. Are you going to want to carry dripping dishes through another room? Does it have a counterspace for setting things down while you unload or open doors? I don’t know…just sounds awkward and like it wouldn’t get used much. But I’m lazy. :smiley:

I actually have one of the ones Elemenopy is talking about, and that would be my first go-to solution.

It hooks easily up to your sink. We have ours on a little table in the corner of the kitchen that easily slides over to the sink, because our counters don’t actually have enough room. It’s been great so far, I’d recommend it - just make sure you keep the trap cleaned, because it fills up faster than a full size dishwasher.

You are best to buy the dishwasher first. THEN see what type of connection it has or comes with. And take that to the hardware or home improvement store to get whatever adapters are needed to connect to your existing line.

Stores typically carry the faucet end of the connection (dishwasher hose snaps onto this). Note there will be threads on the inside as well as outside of some dishwasher faucet adapters!

you may have a problem with running both the washing machine and dish washer at the same time. They both have discharge pumps so it’s not easy to calculate flow rate going into the drain.

Why not just use the portable the way it was intended so you don’t have to mess with the existing plumbing?

Ooops! I forgot about the portable dishwasher discharge!

That could be a problem. It is designed to connect to a kitchen water faucet, then drain directly into the sink below that.

You can see it draining at 3:16 in the following video.

[quote=“Me_Billy, post:9, topic:771734”]

Ooops! I forgot about the portable dishwasher discharge!

That could be a problem. It is designed to connect to a kitchen water faucet, then drain directly into the sink below that.

You can see it draining at 3:16 in the following video.

Dishwashers are usually hard connected to drains unless a portable one dumps into the sink. Washers usually dumped loosely into a drain. If they are on the same line then there is a risk of exceeding drain flow. The loose drain connection would be the point where it overflows.

Thanks for all the replies.

There is not enough space on my counters for a countertop dishwasher, nor room in the kitchen for a full-size portable to move around. But there is space on the service porch, which is only a few steps from the kitchen sink. There is a level of inconvenience involved, but far less than actually doing all the dishes.

I’m not that concerned about the volume of dishwasher discharge on its own–it would drain into a smaller pipe through the kitchen sink than it would on the service porch. I’m wondering about the dishwasher AND the clothes washer draining at the same time through the standpipe, and I think I should probably NOT run them at the same time.