Good Finds, My friend
The WM 5 uses the same pump assembly piece for piece as the 18, 19 and 20 series Kitchenaid dishwashers. It will drop right into position in your WM-5. Remember there are 2 or 3 spring clamps that clamp it against the washtank and it would be easier to replace it before installing the machine.
Does your machine have the heating element in the sump or is it a model without it?
My best friend has a FFW unit in his kitchen which is basically the WM5 modified for any Fast Foood operation. Hobart made the FFB, FFM and FFW for the Burger Kings, McDonalds when they still saw fit to sanitize the trays we eat off of!
His has the built in soap and rinse dispenser pumps so he uses liquid detergents and such.
He also modified his machine to bypass the booster tank and draw directly off his hot water supply as well as he can interrupt the timer for extended washes. Works well for him.
Like Toploader stated, the UM had a small washchamber but you will be able to fit plates and such in it and it will do a great job,but you should really make sure you can get at least 150-160 degree water to it. Otherwise the soils won't be removed and they will not flash dry properly.
On the WM5 you can use it without the booster and save alot of electricity by just disconnecting the heater leads. If your water is up there already, why bother making it even hotter?
It uses like 35 amps to heat that water tank so you will need at least a 50 amp 220 volt line to it with 4 wires. 2 hots,a SEPARATE, LOAD CARRYING NEUTRAL AND A SEPARATE GROUND.It does not delay the wash or rinse if the booster tank is cold! If you elect to not heat it, you will want to run at least a cycle to get the water up to your max available temp. That was also why my friend added additional solenoids and switches so he could get that into the machine without going thru the booster at all which is about 6 gallons in capacity.
You may just be able to fit the 18,and up lower basket into the WM5, though I think it may be a bit too long as the tank is not the same dimension as the dometic machine,(note the cutout for the washarm in the back) but give it a try,or maybe another rack from another manufacturer.That way you get some versatility out of it and get the dishes done even faster!
You have some cool projects to play with so keep us in touch.
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