You may forget to put something in the dishwasher and decide to quickly open it and put the item in, only to see a reddish glow coming from the bottom of the tub. Or maybe you notice a burning smell during one of the cycles of the dishwasher. Or weird whirring noises.
In this article, we will look particularly at the reasons why the heating element is glowing red, and how to test and remove it for replacement, or check other parts which may be affecting it.
Heating Element in Dishwasher Glowing Red! (What to do?)
After the cycle of the dishwasher is complete and you notice the heating element is glowing red, then there seems to be a fault, most likely with the control board. The element should have switched off automatically once the drying function is complete.
While most heating elements do glow orange or red as they supply the required heat to carry out certain processes, they should automatically cool down after that process has ended.
It is also not advisable to open the dishwasher door mid-cycle (in case you wanted to check on the heating element) as the hot water can cause burns. However, with newer dishwashers, safety mechanisms are usually put in place to prevent such accidents.
Why Do Heating Elements Glow Red?
It is normal for heating elements to glow in appliances like ovens, toasters, heaters, and dryers. When the heating element is connected to electricity, it gets hot and starts to glow as the electric current flows through a high resistance.
Heating elements in the dishwasher are made up of certain alloys, such as nichrome that have a high resistance to electricity, as opposed to having high conductivity.
Heating elements in the dishwasher also have a ceramic coating.
Heating elements in dishwashers have 3 functions:
|• To heat the water to a high temperature to kill germs and bacteria.|
|• To ensure dishes are effectively cleaned. Hot water is essential to get rid of dried-up food and oil stuck on the plates and utensils.|
|• To dry the clean dishes.|
Signs Of a Faulty Heating Element
You will know if the heating element is not working if the following occurs:
1- You notice that the dishes are not very clean at the end of the cycle.
Your dishwasher may be connected to the hot water line, but this may not be hot enough to get the dishes perfectly cleaned and sanitized (Dirty dishes can also be a sign of overloading the dishwasher).
2- Dishes will be cold at the end of the cycle.
3- The dishes will also not be dry.
What Can Cause the Heating Element to Malfunction?
There are several ways in which the heating element can stop working, as listed below:
1- A Short circuit Caused by Overvoltage
Faulty wiring or a short circuit can damage the heating element. Unplug the machine and test the plug, control board, and heating element wires with a multimeter.
2- Limescale Caused by Hard Water
Limescale build-up on the element causes it to work inefficiently.
The best way to clean the limescale is by pouring vinegar or lemon juice into a bowl and then running a cycle without any dishes.
The element can eventually burn out. You may notice a burning smell coming from the dishwasher during the wash cycle.
In this case, it is better to stop the cycle and let the element cool down before checking it.
4- Faulty Thermostat
Thermostats regulate the level of temperature throughout the cycle.
If it is faulty, the dishwasher will not be able to sense when the heating element needs to be switched on, keep the water at the required temperature and then switch it off.
5- Control Board Issues
The heating element may not turn off if the control board is faulty. The control board may need to be fixed or replaced.
If the control board senses a fault has occurred with any part of the machine, it should show up on the screen as a fault code. The fault codes and solutions are explained in the dishwasher manual.
How to Remove and Test the Heating Element?
Part One: Removing the Heating Element
STEP 1: Disconnect the dishwasher from the power source.
STEP 2: The heating element is a thin circular tube, usually on the base of the tub. Remove the cover (if it is covered) and the lower dish rack.
Caution: Always wear disposable gloves when touching the element. The oils from the skin can damage the exterior covering.
STEP 3: The element has two terminals that go into the base of the dishwasher. Make a mental note of where they go through.
STEP 4: Locate and remove the bottom plate of the dishwasher. You may have to place the dishwasher on its back to access the wiring.
STEP 5: Locate where the 2 terminals of the heating element come through. There will be a wire connected to each.
Label each side for easier reconnection. Untwist the wire nuts to disconnect the wires.
STEP 6: With a wrench, remove the heating element mounting nuts. From each terminal, gently pull the wire off.
STEP 8: Remove the heating element.
Part Two: Test the Heating Element
STEP 1: Check the element to see if it is broken or burnt out. This is usually visible.
STEP 2: If nothing is visible, carry out a continuity test using a multimeter.
Continuity means a continuous electrical path is present in the element. This means that it is in working order.
STEP 3: The multimeter device should be set to the lowest setting of ‘ohms of resistance’.
Touch each terminal to the probe.
a. If the reading is between 10 and 50 ohms of resistance, it proves that the element has continuity and is functioning properly.
b. If there is no change, or the reading is between infinity and zero, it means the element has burnt out and needs to be replaced.
How a Dishwasher Functions
It is important to identify the various stages of cleaning that are going on in the dishwasher, so any faults can be identified more easily.
The dishwasher is connected to the hot water line, and there are sensors to ensure water is heated by the heating element to the correct temperature, typically between 130-145 degrees Fahrenheit.
The dishwasher does not actually fill up with water as you may think. Instead, dishwashers have water jets that continuously spray and clean the dishes.
Sensors ensure the water levels do not go too high and the dirty water is continuously drained away.
The detergent dispenser opens automatically to dispense the detergent.
Sensors also indicate if the dishes are now clean, by monitoring how dirty the water which is being drained away is.
The last stage is drying. The heating element elevates the temperatures to ensure dishes are efficiently dried. There are 3 ways the dishwasher can do this:
1- The heating element heats the air to elevated temperatures. However, the utensils on the bottom rack dry up more effectively than the ones on top.
2- Some dishwashers come with a fan. The heating element heats the air, and the fans ensure the even distribution of the hot air so that all the utensils get dry.
3- Bosch uses zeolite in some of its series of dishwashers. It is a type of mineral which produces heat when it comes into contact with water.
Can You Use the Dishwasher with a Faulty Heating Element?
Ideally, you should not use the dishwasher if the element is faulty. If you happen to use it, the dishes may not be properly cleaned and dried. They will also come out cold. It is advisable to replace the faulty element before using the dishwasher again.
Modern Dishwashers with Energy-Saving Technology
1- In the final rinse, the water is heated up to high temperatures to make the dishes hot.
2- The stainless-steel tub starts to cool, forming condensation. This causes the water to drop to the bottom of the tub and is then drained away.
This system is more hygienic and energy-efficient.
A Few Tips
1- Avoid putting plastic, especially on the bottom rack. This can fall on the heating element and melt, causing it to smell. It will be a hassle to clean the dishwasher heating element.
2- Avoid putting plates and utensils that are heavily caked with food. The food particles can clog up the water jets or filters which can then malfunction.
In a Nutshell!
If you test and find that the heating element is faulty, it can easily be replaced, which is better than replacing the dishwasher itself.
Always ensure you follow the instructions as per the manual, otherwise, any DIY jobs can nullify your warranty.
If you are unsure of replacing parts yourself and testing them to see if they work, hire an electrician to sort out the issues for you. It may be slightly expensive, but cheaper in the long run as you avoid buying a new dishwasher.
Modern dishwashers are more efficient at saving energy and water. Shop around for a budget-friendly effective dishwasher if you do need to replace it.