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Is your dishwasher not heating water?
Don’t worry, I’ve been there too. I know how annoying it can be to have this happen. After all, cold water simply cannot wash dishes as effectively as hot water.
If your dishwasher is not getting hot water, make sure to check the drain filter isn’t clogged and the hot water supply works elsewhere. If it does, the hot water might be due to a faulty thermostat, heating element, or circuit board.
Read on to go through each of the possible causes and solutions.
6 Reasons Why Your Dishwasher Is Not Heating Water
There are different reasons why your dishwasher is not getting hot enough. Some of the most common are:
#1 The Drain Filter Is Clogged
The drain filter in your dishwasher is designed to capture and trap scrap particles of food, dirt, and debris that come off of your dishes as they are being washed.
When the filter gets too dirty or becomes blocked, the suction power of the dishwasher’s motor will be significantly reduced. As a result, the unit’s ability to heat up may be impacted.
Therefore, take a look at the drain filter to see if it is severely dirty and/or clogged. If it is, remove it from the dishwasher. Fill the sink with warm, soapy water and allow the filter to soak for about 30 minutes to an hour. For a more heavy-duty cleaning, use white vinegar.
Before replacing the filter, use a damp cloth to clean the area around where the filter goes in the dishwasher to remove any left-behind food particles.
Rinse the filter thoroughly and replace it in the dishwasher. Hopefully, this will solve the problem and the water in your dishwasher will heat up now.
#2 The Dishwasher Is Not Connected to the Hot Water Supply
Some dishwasher models need to be connected to the hot water supply to function properly. In fact, some of them won’t even start the wash cycle if the water is too cold.
So, please make sure your dishwasher is connected to the hot water supply and run hot water at the sink before starting the cycle.
But, if your dishwasher is hooked up to the hot water supply and is having trouble heating up the water, then you should take a look at the supply line as opposed to the dishwasher itself. The supply line may be kinked or damaged, requiring repair or replacement.
#3 The Thermostat Is Defective
The thermostat is an indirect component involved in heating the water in your dishwater, as it is responsible for informing other dishwasher components like the heating element about what temperature the water should be.
Therefore, if the thermostat is defective and unable to “speak” to these other components, then the water temperature will not be accurate throughout the wash cycle.
The dishwasher essentially won’t know when to turn the heating element on or off in order to keep the water at the necessary temperature to wash the dishes properly. There will be no regulation of temperature whatsoever.
The good news is that it is relatively easy to test the condition of the thermostat. You’ll just need a multimeter to test for continuity. Please check the manufacturer’s manual to determine the correct resistance reading and find the right terminals to check.
If you can’t find the manual, don’t worry! Take a look at our detailed guide on how to find any product’s manual online.
If the problem is indeed the thermostat, the good news is that it is a relatively inexpensive part to replace. However, it can be challenging to access as it is located underneath the appliance.
#4 The Heating Element Is Faulty
If you determine that the thermostat is not the problem, then your issue may be the heating element, which means the heating process inside of the dishwasher itself.
This is an issue that can occur regardless of whether your dishwasher is hooked up to the cold or hot water supply.
The heating element is responsible for more than controlling the temperature of the water, as it also aids in the drying of the dishes. This component is generally built to last for some time, but it is possible for it to burn out or become damaged as a result of an electrical fault.
The resistance levels of the heating element can be tested with a multimeter. The readings that you see on the multimeter should be somewhere between 15 and 30 ohms. If the multimeter is reading anything higher or open, indicating that the heating element suffered some kind of damage such as a broken wire or blown fuse, then it needs to be replaced.
Similar to the thermostat, the heating element is a cheap part to purchase. In addition, if you are good with your hands, it won’t be a difficult component to replace. Otherwise, you should leave the repair to a professional service repair person.
#5 The Electrical Wiring Is Damaged
All of the components of your dishwasher are connected by electrical wiring. Without those electric wires, your dishwasher would not work—at least not properly.
Over time, these wires can deteriorate, especially as a result of mechanical issues and excessive heat from the electrical current.
Due to this deterioration, your dishwasher may stop heating. If this ends up happening and the electrical wires are the cause, they will need to be replaced.
This is something that you can do on your own, but you should only do it if you feel comfortable doing so. Otherwise, it is recommended to have a professional perform the repair.
#6 The Circuit Board Is Malfunctioning
The circuit board plays a very important role in the overall functioning of your appliance, as it is essentially the brain of the dishwasher. The circuit board is responsible for the management of all of the unit’s functions, such as the motor, water, heating, etc.
Therefore, when something is wrong with the circuit board, something is amiss with the entire dishwasher. If you have checked all of the other components listed above, and it all appears fine, then the problem with your dishwasher not heating up water properly could very well lie within the circuit board.
Because you are essentially dealing with the brains of the entire unit, it is recommended to have a repair technician assess and diagnose a circuit board issue with your dishwasher.
Conclusion
Thank you for reading this article, and hopefully, you have now concluded what is wrong with your dishwasher and why it wasn’t heating up the water.
When you run into any other issues with your dishwasher or other home appliances, please check out our other articles.