Why is my dishwasher not cleaning properly? 11 fixes

After a big family meal, there’s nothing more irritating than opening the dishwasher to see that everything inside is still dirty. Glasses are dull and cloudy. There’s bits of dried food on the plates and between the prongs of forks. Yuk. If you’ve got a dishwasher not cleaning or rinsing properly – don’t panic. There are loads of things you can do before opening your wallet or purse for a new machine.

Rinse your dishes before loading

It may sound obvious, but if you want to make your dishwasher clean better, this is the first thing you should do if you’re not doing it already. While dishwashers can break down food particles if necessary, don’t forget that your dishwasher is not a rubbish bin. Removing leftovers from crockery and giving items a quick rinse before loading will massively reduce the likelihood of dried food on plates.

Clean the filter

Not all dishwashers have a self-cleaning filter. If yours doesn’t, your dishes will be constantly circulating in dirty water and old food particles – ew. Make sure to clean out the filter regularly in accordance with the manufacturer’s instructions.

Dishwashing not cleaning – spray arm blocked

Depending on your machine, you may have one or two spray arms. A spray arm blockage will dramatically reduce its rinsing and cleaning performance.

In accordance with the manufacturer’s instructions, take the spray arm out and clean it. You may be able to use a cocktail stick to remove limescale and food residue.

Load dishes carefully

Be sure to load dishes so that you get the best possible result. Certain things may have a recommended location where to load them.

You should also make sure that larger objects don’t obstruct the spray arm and stop it from rotating. Depending on your machine, you may be able fix this by changing the height of the racks.

Dishwasher not cleaning – water temperature adjustment

Setting the dishwasher’s program to a hotter temperature will make it easier for fats and food particles to dissolve and could fix the issue. A good temperature is 50 degrees Celsius or 120 degrees Fahrenheit or higher.

Broken tablet/soap dispenser

Many dishwashers have a small compartment in the door that releases the tablet or cleaning agent into the machine at a certain point in the cycle.

If this mechanism isn’t working properly, it’s definitely going to have an impact on how clean things are. An obvious symptom is a partially dissolved tablet. You may be able to get around this issue by placing the tablet directly in the machine within your things.

Dishwasher not cleaning – vinegar cycle

Make sure that the inside of your dishwasher is also clean. You can remove any weird smells, fats, soap scum, limescale, and food particles that may have accumulated over time by running a dishwasher vinegar cycle. To do this, simply fill a dishwasher-safe container with 1-2 cups of distilled white vinegar, place inside the machine with no other crockery, and run a normal cycle.

Once it’s done, open the door and let it dry.

Faulty water supply or inlet valve

Issues with the water supply will obviously affect your dishwasher’s ability to clean. Make sure that its water supply is good.

If you hear banging or vibrating noises, this is water hammer and could indicate an issue with the inlet valve. You may require a tradesman to diagnose and repair it.

Dishwasher not cleaning? Try a rinsing agent

If you can use a rinsing agent with your dishwasher, it’s definitely worth giving a go. A rinsing agent – or surfectant – is a substance that reduces the surface tension of the fluid that contains it. By doing this, it makes the water less likely to form drops, and thus, less likely to leave limescale streaks and clouds.

Try a different detergent

Changing to a higher quality detergent or tablet may give you better results.

Use a water softener

If you live in a hard water area, it could be worth installing a water softener. This will reduce the amount of calcium in your water, and make it much less likely to form limescale deposits. Other appliances in your home may also benefit from this, like the washing machine and the water heater or hot water cylinder.