How does a dishwasher work

A dishwasher works in the following way: At the bottom of the dishwasher a layer of water is pumped, this layer of water is heated by a heating element. The detergent is added to the water after a certain amount of time. After this has happened the dishwasher starts pumping the water up through the spray arms, in this way the dishes are washed clean. When this process is finished, the dirty water is removed and the dishes are rinsed once more with clean water. This water is also drained off and voilà, all the dishes are shiny clean again!

How does a dishwasher work



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A wash geek since 2017

The different parts of a dishwasher

To answer the question, “How does a dishwasher work?”, you first need to know the different parts of the appliance.

The heating element

The heating element of a dishwasher consists of pieces of metal that convert electricity into heat. This heat is used to heat the water to the temperature of the dishwashing program that you have chosen.

The pump

To make sure that the heated water is squirted through the dishwasher and to drain the dirty water again, a dishwasher also has a pump. The motor is also the part that pumps the water through the spray arms.

Spray arms

The spray arms look like a kind of propeller and you can find them at the top of your dishwasher. The water is pumped through the spray arms at such a high pressure that they start to spin around and spray all the water over your dishes.

How does a dishwasher work?

Most dishwashers perform the following steps to get your dishes clean:


Before the washing up begins, a layer of water is pumped onto the bottom of the dishwasher. This is heated by the heating element, which is also located on the bottom.

Rinse dish

First, your dirty dishes are thoroughly rinsed. For the rinsing process, the dishwasher has heated clean water and this is now sprayed past your plates, cutlery and glasses at high pressure. The water spreads out over your dishes via the spray arms. The dishwasher builds up pressure, causing the spray arms to rotate and the water is sprayed out of the small holes. Your dishwasher will add the detergent itself during this process. The detergent block is released from the door of your dishwasher and mixes with the hot water and helps rinse the dishes. The spray arms continue to spin and add clean water until all the suds are rinsed away.

Dry Dish

You slide your dirty dishes into the dishwasher and you take them out clean. It’s not always completely dry either. Most dishwashers blow warm air through your dishes after the rinse cycle, so they are almost dry. Large items such as pots and pans may need to be dried with a tea towel.

Maintaining the performance of your dishwasher

Maintaining the performance of your dishwasher is important to keep the spray arms clean. If debris gets stuck on them, it will be flushed through your dirty dishes at high pressure, leaving them on your dishes.

When loading and unloading the dishwasher, also make sure your dishes aren’t too dirty. Too much food residue can cause the pump to clog. A dishwasher will not work as well if the pump is blocked and the water starts to smell.

Don’t put anything in your dishwasher that is particularly sensitive to heat, such as plastic containers. Especially in the lower rack, they can melt and block the mechanisms behind them.

Picture of Yannick

A wash geek since 2017

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