Dishwasher not Cleaning Well

Reasons, Solutions and Prevention

Don’t be upset if your reliable helper leaves stains or pieces of food and doesn’t wash the dishes to a "squeak" anymore – it’s too early to call a specialist yet. You can fix most problems by yourself.

In this article, I will explain the reasons and give some troubleshooting tips. All the reasons can be divided into categories that will be described below.

Human Error

When we buy an appliance we read the manual and try to follow it. However, as time goes by we stop paying attention to the printed instructions:

• Putting inside the dishes with large amounts of dry food. As a result, the dishwasher can’t deal with it.
• Choosing the wrong detergent. Don’t try to save and use a hand-washing cleanser. Excessive foam will cause a malfunction at the worst case and leave stains at the best.
• Using the wrong program. Some people make the dishwasher clean too dirty dishes in economy mode.
• Trying to put the items too close to each other (more items) on the rack. Water from sprinklers (the impeller) doesn’t reach all corners.

Apart from that, you should certainly make sure to put a tablet and rinse aid, if necessary.

Technical and Operational Reasons

You’ll have to do some work on the unit yourself to find out the issues. In case of a serious breakdown, it’s better to call a specialist. What may cause poor cleaning of dishes?

Clogged inlet or drain filter

The inlet filter is installed on the unit at the cold water hose connection point. It prevents small scales and metal chips in water supply lines from getting inside the unit.

Disconnect the hose (shut off the water supply in advance), remove the filter from the installation place, and clean it, for example, with a hard toothbrush.

The drain filter is installed at the bottom. Unscrew and inspect it. A strainer clogged with pieces of food and fat will not let through the sufficient amount of water reused during the washing. I recommend cleaning the strainer using a sponge in water with soda and salt at least once a week.

Faulty heating element

In this case, the water does not heat up and fails to dissolve the fat on the dishes even with the detergent. It significantly reduces the cleaning ability.

If you have some technical skills and the required device (a tester), you can check the continuity of the circuit and functionality of the heating element, as well as replace it by yourself.

A simple test: When you open the dishwasher door (after a complete program, not only rinsing) and you don’t see any steam coming out, there’s a big chance of the heating element being faulty. This shall be checked immediately after washing.

Scale can be another reason for a faulty heating element. Scaling is typical of all appliances, but water hardness defines how soon it happens.

Clogged sprinkler nozzles

The reason for it can be hard water or pieces of food. Water hardness can be controlled according to the manual if the model supports it.

The selected value changes the delivery rate of regenerating salt added to the ion exchanger. The water can be softened manually as well — to do that add the mixture to the container.

Impellers can be easily removed and installed. Wash sprinklers in warm water with soap and clean the nozzles, for example, with a toothpick.

Unfortunately, sometimes a failure requires professional diagnosis:

• faulty temperature sensor that controls the heating element;
• The circulating pump is faulty and water is not delivered to the sprinklers preventing them from rotation;
• Electronic module software failure.

To sum it up, the chances of low-quality dish cleaning can be reduced by regular dishwasher maintenance.

Currently, it’s enough to use preventive chemicals that prevent deposits and scaling of the heating element.

We recommend using the dishwasher and choosing the detergents according to the manual.