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Why is your dishwasher not cleaning properly?

Bram14 SEPTEMBER 2025
A dishwasher stands open in a kitchen with light grey cabinets and a dark countertop. Dishes fill the dishwasher racks.

Do your glasses come out of the dishwasher dull or do your plates remain greasy? Then something isn't functioning quite right. Don't panic, you don't have to call in a handyman or look for a new dishwasher right away. The problem is often easy to identify and solve. In this article, we'll help you on your way to clean dishes.

Why don't your dishes come out of your dishwasher clean?

Before you call a technician because your dishwasher is not working properly, there are several things you can check and solve yourself. Let’s go through the possibilities together:

The inside of a clean, empty dishwasher with a metal filter and a grey spray arm. No brand is visible on the appliance.

Spray arms are blocked

The spray arms in your dishwasher rotate and spray water to clean your dishes. If the spray arms are blocked because the dishwasher is not loaded correctly, they will not be able to rotate. So always check that they don't bump into your dishes. Another possible cause is that the holes of the spray arm are clogged and therefore allow little or no water to pass through. Clean the holes with a toothpick and rinse the spray arms thoroughly.

A close-up of the salt compartment and metal filter inside a dishwasher. No brand is visible on the appliance.

Not enough dishwasher salt or rinse aid

Dishwashers need salt to soften the water and prevent limescale. If your dishes are not cleaned properly, check whether the salt reservoir is sufficiently filled. How often you should do this depends mainly on the water hardness in your region. Do you use your dishwasher every day? Then refill the dishwasher salt every few months, or when the machine tells you to.

Rinse aid also helps the dishwasher to clean and dry your dishes without stains. We therefore recommend that you regularly refill the rinse aid reservoir of your appliance. Many dishwashers have a cap with an indicator in the reservoir. It changes colour or shows a moving marker, depending on the level of the brightener. Consult the manual of your device to know how the indicator works for your model.

Plates, cutlery and wine glasses are clean and neatly arranged in the rack of a dishwasher. No brand is visible on the appliance.

An improperly loaded dishwasher

For optimal results, arrange the dishes in your dishwasher in the recommended way. This way you can be sure that the water can reach all dishes properly. Place bags, bowls, and glasses in the top drawer of the machine, leaving enough space between items. You can use the lower rack of the dishwasher for larger cooking utensils, such as plates, pots, pans, and bowls. Place trays and cutting boards on the side, so you don't block the spray arms of the device. Put cutlery in the corresponding basket or drawer that the dishwasher is equipped with.

A finger presses the eco button on a dishwasher. The display shows 2:19 and cups are in the top rack. No brand is visible.

Incorrect dishwasher program

If you choose a low-temperature cycle repeatedly, the filters and water pipes of the dishwasher will not always flush properly. This can prevent your dishwasher from cleaning like it is supposed to. Therefore, you should regularly alternate between low-temperature and high-temperature dishwasher cycles. Some dishwashers also have a special cleaning program, which will leave your dishwasher feeling and smelling like it is brand new.

A person wearing blue gloves and an apron is cleaning the inside of an open dishwasher. No brand is visible.

Check the filter

If you don't pre-rinse your dishes, food residue and grease often end up in your appliance. These remain in the filter and can cause a blockage. As a result, the dirty water does not drain properly and continues to circulate in your dishwasher. Rinse the filter under running warm water. If necessary, use soapy water for an extra thorough cleaning.

A dishwasher tablet sits in the open detergent compartment of a dishwasher. No brand name is visible on the appliance.

Dishwasher tablet does not dissolve well

Does your dishwasher tablet not dissolve properly? Here are the most common causes:

  • The dispenser is clogged or broken.
  • The water is not warm enough.
  • Tablet might be low-quality

Tip: Is the problem not solved? Then try resetting the water stop of your dishwasher.

How do you make sure a dishwasher cleans properly?

A person rinses a dishwasher filter under running water at a metal sink. No brand is visible on the filter.

Cleaning your kitchen appliances regularly is essential to keep them working properly. This also applies to the dishwasher. This is how you clean your appliance:

1. Clean the spray arms by removing them from the dishwasher and rinsing them under the tap. If necessary, remove stubborn dirt from the holes of the spray arms with a toothpick.

2. Clean the filter of the dishwasher. This catches leftover food residues and can become clogged. Read the manual of your appliance to learn how to remove the filter from the dishwasher and clean it with water and dish soap.

A person wearing a yellow cleaning glove wipes the inside of an open dishwasher with a pink cloth. No brand is visible.

3. Polish the rubber seal of the dishwasher door with a damp microfiber cloth. Then leave the door open for a few hours so that the rubber can dry properly.

4. Clean the inside of the dishwasher with a detergent. You can use a sponge and a special dishwasher cleaner for this. Alternatively, pour a splash of household vinegar into the bottom of the machine or add a tablespoon of baking soda to the soap dish. Then run the appliance at a high temperature without dishes.

5. Descale the dishwasher with a descaler. Just like in step 4, you let the dishwasher run a cycle at the highest possible temperature.

Discover our dishwasher accessories

What are the risks of a dishwasher that is not clean?

A person smells the inside of an open dishwasher in a modern kitchen, with dishes in the rack. No brand is visible.

You can immediately recognise a poorly functioning dishwasher by dishes that don't come out of the appliance clean. That is annoying, but ignoring the problem can have bigger consequences. For example, your dishwasher can start to smell in the short term, due to the bacteria that accumulate in your appliance. In the long run, poor maintenance reduces the lifespan of your dishwasher.

Our advice for a dishwasher that is not cleaning properly

If your dishes suddenly start to come out of your built-in dishwasher dirty, there's no need to panic. You can easily solve many problems yourself. Go through the options at the top of this article and take precautions to avoid problems in the future. Is your device not working properly yet? Check out our Smartbar. Problems persist? We're happy to help you choose a new dishwasher.

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