Commercial Dishwasher Install

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chriswrightcycles

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Hello all. First post here to the forum.

I picked up a commercial Hobart under-counter dishwasher at auction a couple years ago for a song with hopes of installing it in my home. We feel confident about doing the electrical work to get this set up but the plumbing connections have me scratching my head. Hoping someone reading would be willing to share their thoughts. Also I should mention in advance that I do not know plumbing terms but will try my best to share the necessary info. The copper tubing that is currently supplying our (old) dishwasher has an OD of 5/8" (which I believe is considered 1/2" trade sizing) and connects to the dishwasher with a 3/8" braided stainless hose. The new Hobart dishwasher is equipped with a 3/4" female garden hose fitting which is not compatible with the existing 3/8" fitting that is brazed to the supply line. My question is this, is it bad practice to connect the existing 1/2" water supply to the 3/4" Hobart garden hose fitting using an adapter? I'd imagine that water pressure might be reduced but are there any other issues that I should be aware of?

Thanks in advance,
Chris
IMG_3753.jpgIMG_3754.jpg
 

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Jeff Handy

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I think you can find a 3/8 compression inlet to garden hose outlet braided supply line.
 

Jeff Handy

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Or something like this, which has 3/8 on both ends, but comes with the garden hose adapter.

You already have a flex hose, but toss the old one, no need for a flood from keeping the older hose.

 

chriswrightcycles

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Thanks Jeff. The braided flex hose on the new machine has a noticeably larger diameter than the hose on my old machine. Are you suggesting that we remove the braided hose on the new dishwasher and replace it with the item you linked to above?
 

Jeff Handy

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Unless you want to cut off your existing shutoff valve, and put on a new valve with a 1/2 inch compression outlet (by soldering or using a compression coupling or a Sharkbite valve) then I don’t see why you would want to re-use the old braided hose.

And how old is the old hose?
It is already aging.
They get stiff and can leak.

Always change the supply hose when changing the fixture, because the fixture might be in use for twenty or more years.

If there is something else I am not understanding about the hose diameter, let me know.

If the old hose has a larger internal diameter, it won’t help fill up faster unless you change the valve to larger also.

You can get new larger ID hoses, if that is your point.

And that link is just an example, you can get hoses like that everywhere, in different lengths, and some have that right angle hose elbow built in.
 

Helper Dave

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I'd highly recommend checking the specs, and manufacturer installation instructions for your model online, too.

They're designed to drain into floor drains with an air break (drain pipe just freely sitting above the drain), and they spit out a lot of water fast when they drain. I used to use Hobarts when I worked at a coffee place, so I'm familiar with them a bit. I'm pretty sure typical residential drain set-ups will not cut it. I know if you've got it hooked up via air gap on your sink drain, or to your garbage disposal that there's little chance it'll handle the drain output. So yeah, do some reading, and see what you'll need.
 

Geofd

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I'd highly recommend checking the specs, and manufacturer installation instructions for your model online, too.

They're designed to drain into floor drains with an air break (drain pipe just freely sitting above the drain), and they spit out a lot of water fast when they drain. I used to use Hobarts when I worked at a coffee place, so I'm familiar with them a bit. I'm pretty sure typical residential drain set-ups will not cut it. I know if you've got it hooked up via air gap on your sink drain, or to your garbage disposal that there's little chance it'll handle the drain output. So yeah, do some reading, and see what you'll need.
If it’s draining into pvc it won’t take the heat I there is probably a booster that raises the temp to above 150 degrees
And depending on how chemicals are added to the system you may need a testable backflow preventer
You may want to contact Hobart tell them what model you have and if it will work with your set up I think the
Electrical is totally different also
 

Mitchell-DIY-Guy

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Guaranteed if you contact the manufacturer they will tell you that this is not suitable for use in a residential environment.

However that doesn’t mean you can’t get the specifications and try to make it work...

There’s some thing about a dishwasher that has a cycle time measured in minutes that can be very appealing...
 

breplum

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You need a 12 x 12 floor sink with its own 2" p-trap. What you have is totally unsuitable for a residence unless you want to spend the money to hire a plumber to do what is necessary.
 
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