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How Do Dishwashers Work?

A collage of dishwasher with dishes.

The dishwasher is a device that both washes the dishes and dries them. Thus, discovering the principle of the operation of a dishwasher is equivalent to understanding how it washes and dries. The principle of the operation of a dishwasher is based on certain elements.

If you wish to take advantage of what this device offers, you will take care to master a few basics relating to its operating principles. It is in this way that we can also detect any problems inherent in the operation of the device.

Related: Types of Dishwashers History of the Dishwasher How Much Water do Dishwashers Use? | How Do Portable Dishwashers Work?

A Dishwasher: How Does It Work?

If the appliance is equipped with a natural condenser, the hot water from the last rinse evaporates. A mechanism then offers the possibility of allowing the vapors to flow along the walls to be subsequently evacuated by the drain pump. It is then possible to start the drying process by means of a turbine.

In this context, the fresh ambient air “captured” by an outlet that can be found at the back of the tank is amalgamated with the hot and humid air of the tank while the lukewarm air thus obtained is evacuated on the front of the device. This is how the dishwasher accelerates heat exchange.

The Condenser

With the water condenser, vapor condensation takes place on the curtain as well as on the cold walls of the device. It is then a drain pump which evacuates the water thus obtained.

The condenser outside the tank, for its part, works via a collection tray that can be found under the tank. This drip tray is intended to collect the condensates. Evacuation is also carried out by a drain pump.

The Inner Workings

Even though the operation of the dishwasher seems quite simple, the mechanism that arises from its inner workings is quite complicated. First, the machine is connected to an external water supply controlled by a tap. The water then passes through the various parts of the device before entering the tank.

The next step is the heating of the water by resistance, which brings it to an ideal washing temperature. The water then goes to the spray arms to spray the baskets and dishes.

During this process, it should be noted that the distribution of the products takes place in a closed circuit between the tank and the reels. Once cleaning is complete, the wastewater is drained out of the machine through the drain hose.

The General Process

To begin with, the dishes are placed in two baskets inside the machine. Then, the washing arms of the machine are responsible for spraying the utensils with water.

The reels will turn on themselves. This sweeping of the reels makes it possible to degrease services and cutlery in the best way. Besides, there are rotating parts that are located on the lower and upper part of the cabin. The rotating parts at the bottom spray the utensils with high-pressure water.

It should be remembered that this high pressure is essential for stubborn residues on plates, pans or dishes. As for the rotating part of the upper part, it diffuses water at low speed. This speed is intended for fragile dishes such as glass or plastic.

However, we must remember that the dishwasher does not clean black, grilled or burnt. To clean them, it is necessary to scrub them by hand before putting them in the dishwasher.

The Different Washing Cycles

A dishwasher cannot be limited to water sprinkling only. The dishwasher goes through several phases to get your utensils cleaner. Among other things, a distinction must be made between the maintenance products poured into the machine to optimize the cleaning process.

As soon as the machine is started, the first phase begins with a pre-wash, generally cold, which aims to moisten the dishes. Then the hot wash takes over. It is at this stage that the washing product spreads over the baskets.

When this phase is complete, the water will be cooled. Note that at this stage, the rinse aid is released in the last phase of rinsing. Also, we must know that this process depends on the program activated on the machine. Each program is specific, depending on the nature of the dishes.


The dishwasher will have the function of controlling the temperature of the water and will trigger or stop the operation of the resistance, as the case may be. Once mixed with the washing product, the water is directed into the tank, is filtered, then returned to the spray arms.

Water recycling takes place continuously until the end of the washing program. After the latter, the wastewater is evacuated by the drain pump of the machine to allow the dishes to be rinsed with clean water.

In this context, it will be noted that the rinsing product contributes greatly to facilitating the flow of water into the parts of the dishes. It works so that the water does not leave whitish traces on it.


A good wash necessarily implies a good rinsing. For this, it should be noted that the ideal temperature will not be below 55°C.

This happens in order to remove fats and pathogens effectively. At the same time, care should be taken to bear in mind that, in general, the rapid drying of dishes requires a temperature above 80°C.


It should be noted, at first glance, that the machine carries out drying of dishes by the principle of condensation. The fact remains that not all dishwasher models go through the drying stage in the same way. This is because said drying varies according to the capacitor, and therefore the dishwasher drying mode.


If you have a dishwasher, it is important to know how it works so you can maintain it for ongoing use.

We hope that you have gained some insight into what goes on inside the dishwasher while in use and some tidbits about the part you can play to ensure that your dishwasher lasts for a long time with how you use and maintain it.