What heats the water in a dishwasher?

That’s heat for the drying cycle. I believe the washer pulls hot water from your hot-water heater like all other appliances. The high-heat setting is most likely a higher hot/cold balance.

From the same source as your shower and clothes washing machine: your gas or elsctric water heater.

@astro why does that get so much hotter than my shower can ever get? Is there some kind of limiter on the faucets?

There’s gotta be something that heats the water further.

In the U.S., many hotwater heaters are now physically limited to 120 degrees F. But dishwasher detergent doesn’t fully activate until 140.

Anti-bacterial and Hi-Temp Scrub gets even hotter.

My guess is that the dishwasher pulls in hot water from the line and accumulates it in the bottom of the tub. Then, for more heat, the heating element (also down in the tub) heats that water even further.

But I’d really like to know for sure. My guesses have a way of turning out to be exactly wrong.

@rob ok your question is bothering and i needed to know the answer so after some searching heres what i found.

First a pretty picture
When you turn your dishwasher on that basin will fill with water. Then the heating element will heat it up to around 140 degrees F. Then a pump forces the water out of the sprayers cleaning your dishes (YAY CLEAN) and then the water is drained out.

I believe the heating element at the bottom does this. Otherwise, the water would quickly go cold during the dishwasher cycle.

The heating element is used to bring the water temperature up. In some dishwashers, there was a sanitize cycle. This required water to reach 180 degrees, well above the 120 to 140 degree water in a regular household water heating circuit.

Well, even a blind squirrel finds a nut from time to time… sounds like my guess was right. Hooray me! Thanks @uberbat, et al!

And now I know better, too. Thanks, Fluther!

My dishwasher has its own water heater on it. My dishwasher is an LG.

I know from painful experience that that heating element really gets hot. I started to unload my dishwasher last week immediately after the rinse cycle was done. I reached down to pull out the lower rack and accidentally grabbed the heating element. My flesh was seared and it hurt like hell.