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How To Fix A Dishwasher That Doesn't Wash Properly

How To Fix A Dishwasher That Won't Clean Properly


There are many reasons in which your trusty dishwasher is failing to get with dishes clean. Here are some of the possible causes, and tips on how you might be able to fix them without bringing in a costly serviceman:

The Spray Arm

  • It could be due to low pressure from the spray arms. This could be because if the upper discharge housing gasket (seal) may have come loose, or just need replacing all together. You can find this on the discharge cover above the circulation impeller. If you have decided to replace the gasket, make sure you clear the area of any grime and debris so that the gasket can fit securely, and so this problem won't occur again.


  • The spray arm itself could also be the problem. Either the lower, upper, or middle spray arms can all be at fault if your dishwasher isn't cleaning properly. Their function is to spray the dishes with a constant stream of hot water and detergent. If you suspect this isn't happening, check to see that the spray arms can move freely (obviously obstruction from plates, pans or anything large, can cause this problem).


  • The bearing ring for the arm can also wear down or become loose, and this can then cause the spray arm to be wobbly, which will prevent a regular, consistent spray. Also, make sure to inspect the arms for any cracks, or holes, as well as debris like foods or broken plastic/glass. These may be obstructing the holes in the spray arm which can reduce the pressure of the water, or change the direction of the spray. If your dishwasher has an upper spray arm, make sure the spray arm mounting braket has not become loose, cracked or damaged in any way, as this also could impair the quality of the wash.


  • If your dishwasher has a middle spray arm that is attached to an adjustable upper rack, it could be the docking station that is the problem. This part is usally located at the back of the dishwasher on the water supply tube. Its job is to provide water to the middle spray arm. You must inspect whether this is connected securely to the water supply tube, as well as checking the flappers to make sure they can move freely. They must be able to close securely in order to prevent a pressure loss. Also check for any damages like cracks, and make sure to replace the component if necessary.


Other Possibilities

Some machines have a chopper which deals with food left on plates etc, so they can easily pass through the drain. If these aren't chopped properly, the debris will prevent water from draining properly, which will then get recirculated around the machine, meaning food and grime will just go straight back onto your dishes. Inspect the drain portion of the pump, and if you find food debris there, check the food chopper to see if it's damaged.

Water inlet valves can be a cause for many issues, and are one of the most common parts to fail. In this instance, it could be the reason your dishwasher is not cleaning your dishes well, especially if it is not providing the power water level in the tub. You can usually find the water valve at the front of the dishwasher, behind the lower access panel. If the proper water valve at the front of the dishwasher, behind the lower access panel. If the proper water level is not being reached - or worse you have no water at all - then check that the valve is not blocked, and verify the valve is recieving appropriate power during the fill portion of the cycle with a multi-meter. If the inlet is restricted, and the power supply is fine, then it is most likely that the valve needs replacing.

Every dishwasher will have a filter to prevent large foods ending up in the pumping system. Modern machines can half a self-cleaning filter. Usually the filter is located at the bottom centre of the machine and are easy to remove and clean. We suggest doing this regularly to prevent any issues, and if cleaned then your wash should improve significantly, as well as making sure your machine is able to drain efficiently.

Your wash spinner is a small wash arm found on the water feed tube, or sometimes at the rear of the tub. If the spinner comes loose, or is not properly fitted, or damaged in any way, then it could result in your dishes not getting cleaned properly. Make sure it is able to spin freely, and is working properly.

It could also be the heating element which is preventing your dishes from being clean. Obviously, dishwashers need to use the appropriate temperature for the water in order to wash the contents. The heating element is located at the bottom of your dishwasher and of course, its job is to control the temperature of the water in the dishwasher for certain settings or cycles. (Please note however, it is not the heating element that heats the water for an average cycle, and it is important to check your household system is allowing hot enough water to enter the machine.) If hot water is going into your dishwasher, but the temperature drops while the cycle is running, then you may need to replace the heating element. To test if it is working, use a multi-meter.

Finally, it could be your pump's impellers that are causing the issue. The two (the wash and drain) help to circulate and then drain the water. Check them for debris and damage as if they aren't working efficiently, this can affect the quality of your wash.


Spare Parts

To find spare parts compatible with your specific dishwasher, you will need the model (type) number. This is usually made up of a combination of numbers and letters and can be found on the type plate which can be located on the inside of the dishwasher door, or all the way at the bottom (under the door, almost on the floor). In our shop, if you search by this number, you will be shown all the parts we have available that are suitable for your machine. Read here if you need help to find your type number.

Get In Touch

Let us know if this has helped you solve your problem on our Facebook. If you have any questions or queries about the spare parts you might need, then feel free to send us an email at info@fiyo.co.uk, or get in touch with us via our contact form. Remember to include your model (type) number so we can make sure we're searching for the right parts for you.