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Comment by xethos | Hacker News Reader

Haven't worked in a commercial kitchen, and I've been wrong before (in this chain, no less), but how would the water be hotter without a heating element? Consumer dishwashers are plumbed into the hot water, so it can't be a difference in a direct hook-up. Without it's own heating element, I wouldn't assume it has its own built-in and ready-on-demand hot water tank, either.

My last guess is more frequent cycles, meaning hotter water already at the spigot / dishwasher outlet, similar to the consumer recommendation to run the hot water for a minute prior to starting the dishwasher?

Plastics / tupperware were actually what I had in mind lol

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The water is hotter in a commercial dishwasher. I forget the exact numbers but it's substantially more. What the commercial dishwasher doesn't have is an "oven style" heating element running around the perimeter of the bottom (or somewhere thereabouts) to dry the dishes. Most residential dishwashers have this. This is why some dishes say "top rack only". The water coming out the top isn't any different. It's that you're moving the dish farther from the hot element. So a dish that goes through a commercial dishwasher sees higher average temp but substantially lower peak temp.

At least the commercial ones I've been using on and off do not have a drying cycle at the end of the program; they just steam the heck out of whatever is inside, then once the cycle is through, you are expected to remove the tray with whatever you were washing and let it air dry on the bench.

This in contrast to the consumer unit at home which heats the interior of the dishwasher for 45 minutes or so after it has done its washing cycle to dry things while still inside the dishwasher.

Some dishwashers blow hot air to dry, some get the rinse water extra hot, some do neither.

If they're talking about the water being hotter, but not a "stupid heating element that runs to dry", then it sounds like they mean the hot air.

for commercial there are 2 options chemical and temp sanitization. From fda food code has to reach 171F to sanitize. most use a inline OnDemand heater with a couple taps so constant temp is close to 170 but will also pipe off steam to do a final sanitize. restaurants will also hand wash their plastics in a 3 sink setup water only needs to be 110F

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