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Do dishwashers use hot water?

Part of caring for your family is making sure your dishes and utensils get a proper clean after every use. If you use a dishwasher for post-meal cleanup, you may have wondered whether the appliance uses hot water to tackle food residue. Use this guide to better understand dishwasher water temperatures.

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Does a dishwasher heat its own water?

Depending on the model, a dishwasher will source hot water from a nearby hot water valve or heat up cold water with its own water heater.

How does dishwasher water temperature affect cleaning?

For the best cleaning results, the water temperature should be 120°F as it fills the dishwasher. Hot water dissolves and activates dish detergent while helping to break down grease on your dishes.

Some dishwashers have cycle settings like the Hi-Temp Wash or the Sanitize Cycle to raise the water temperature during the wash cycle. The Hi-Temp setting helps to cut through baked-on food and residue, while the higher wash and dry temperatures of the Sanitize Cycle can help kill 99.999% of food soil bacteria.

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How do dishwashers maintain water temperature?

How a dishwasher maintains hot water temperatures varies depending on the model. Some dishwashers use a heating element to heat cold water to the proper cleaning temperatures, while others draw hot water in through the hot water valve.

Can you run a dishwasher with cold water?

If your dishwasher’s water is too cold, your dishes may not be getting the best clean. Dishwasher detergent typically requires hot water to properly activate and dissolve, which is why it is important to ensure that your dishwasher is maintaining the proper water temperature.

Dishes being rinsed with water inside a dishwasher

How do I ensure that my dishwasher's hot water supply is okay?

Typically, you can check your dishwasher’s hot water supply by testing the water temperature of the kitchen faucet. Place a candy or meat thermometer in a glass and fill the glass with hot water from the kitchen sink. If the thermometer reads between 120–150°F, your hot water supply is okay.

What should I do if my dishwasher cannot maintain its water temperature?

If your dishwasher’s water supply isn’t hot enough, you may need to adjust your water heater. For dishwashers installed far from the water heater, it is recommended to run the kitchen sink’s hot water before starting a wash cycle to minimize the amount of cold water in the water line. For more help with your Whirlpool® Dishwasher, schedule a service with a licensed technician.

Shop for Whirlpool® Dishwashers

The right dishwasher can make after-dinner cleanup less of a chore, which is why Whirlpool® Dishwashers have the features you need to get dishes, cookware and utensils cleaned properly. Explore the entire collection to find a dishwasher that’s the right size, color and finish for your kitchen.

Learn more about Whirlpool® Dishwashers

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