One of the regularly used appliances in most homes is a microwave oven. As they are used almost daily, they are prone to malfunctioning.
Different brands are manufacturing different models of microwaves, intending to provide users with better services. However, with time, even the top-notch microwave models show signs of faulty mechanisms. No matter if it’s an LG, GE, Samsung, Maytag, Frigidaire, or Kitchenaid microwave, the machine will malfunction after being in use for years.
A microwave malfunctions due to various reasons. In some cases, the microwave fan keeps running due to a defective thermostat, while some microwave ovens malfunction due to a faulty air filter. There are several reasons that prevent a microwave fan from turning off on time.
In this guide, we have explained the various causes that give rise to this issue. Not just that, we have also discussed how one can fix this issue quickly.
Why Won’t the Fan Shut Off On My Microwave?
When this problem occurs, one wonders the possible causes of this problem. Here is a list of reasons that explain why your microwave fan won’t turn off.
Overusing the microwave
If you have been overusing the microwave for consecutive days, it might malfunction. Usually, microwave ovens have a thermostat which ensures that the microwave vent fan automatically turns off when the microwave reaches a cool temperature inside.
Now, when you overuse the microwave, it takes longer to cool down. If that’s the reason, you don’t have to panic. Stop using the microwave for some time and the fan would automatically shut off.
If you notice that your microwave is getting too hot when being used, you must get it inspected by a professional. Usually, when something is wrong with the control board, the microwave gets overheated.
Kitchen temperature too hot
Is it summer in your area? Is the kitchen too hot? In such times, the microwave takes time to cool down. You simply have to be patient and allow the machine to cool down eventually.
Once the thermostat records the ideal temperature is reached, the microwave fan would automatically turn off.
Faulty air filters
Sometimes the air filters get clogged. The air filters are important as they absorb dirt and dust and prevent them from getting inside the machine. Over time, dirt and dust can build up inside air filters, resulting in a blockage.
Check the air filters if your microwave vent fan won’t turn off. Clean the air filters or replace them with new ones.
Faulty grease filter
The grease filter, just like the air filters can also get blocked by dirt and dust accumulation.
The grease filter absorbs oils and fats from the food that’s being heated inside the microwave and helps the exhaust system to remain clear and clean.
Malfunctioning damper assembly
The function of the damper assembly is to prevent outside air from entering the machine through the exhaust system. The damper is made up of plastic or metal. It opens the exhaust conduit when the vent fan is rotating and closes it when the fan is off.
Now, when the damper assembly fails to do its function properly, it affects the working of the microwave vent fan.
Therefore, inspect the damper assembly and see if anything is stuck inside which is obstructing the component to function properly. Also see if the damper is damaged, cracked, or weak.
The function of the thermostat is to regulate the temperature inside the microwave and turn off the fan when the temperature inside the microwave cools down.
In case, there’s a faulty thermostat, the exhaust fan of microwaves refuses to stop. If you are dealing with a faulty thermostat, we would advise you to get a new one instead of repairing the old thermostat.
Faulty fan motor
Sometimes, the microwave’s fan motor is faulty. Therefore, don’t forget to inspect the fan motor.
How To Turn Off Vent Fan On Microwave?
Now that you know the possible reasons that prevent a microwave vent fan from turning off on time, here is a list of things one can do to turn off the exhaust fan.
Even if you can’t identify the cause of the issue, try out the below-mentioned steps to fix the issue.
Manually switch off the fan from the settings
If you don’t know how to operate the microwave, check the instruction manual and follow the below-mentioned steps:
- Visit “options” settings on the machine.
- Oftentimes, people can’t find “options” on the microwave. If that’s the case with you, press the “control setup” button.
- Now enter the setup mode.
- There, search for “vent fan” and click on it.
- Now switch off the “vent fan”. Your exhaust fan would stop rotating. If you want to turn it on again, do it from “settings” by following the same steps.
Check the control panel
If something is wrong with the control panel, you must inspect it thoroughly. Take the panel out and check the connections. If they seem good, you must clean the board’s connections. You will surely see a ribbon-like cable on the mainboard. Remove that and clean the board’s connections.
After it’s done, place everything in position and check if the microwave vent fan is turning off on time. If the control panel was the cause of the issue, it’s expected to be solved. If not, you must inspect the other components.
Disconnect the microwave from the main power supply
If you notice that the microwave vent fan is not stopping even after hours, disconnect the device from the main source of power.
Unfortunately, doing so would break the current circuit, meaning that the entire device would stop working, including the vent fan. Keep it disconnected for about half an hour before you connect it to the main power source again.
Unclog the filters
We already mentioned how the air filters accumulate dirt and dust over time. It’s important to inspect them and clean them from time to time for the normal functioning of the microwave.
Unclogging the filters is important to ensure optimum performance of the microwave.
Inspect the fan motor
Sometimes the fan motor is faulty and therefore fails to work properly. To make sure the fan motor is in good condition, bring it out and turn the blades manually.
If the blades don’t move freely, consider replacing the fan motor.
Check if the thermostat is in proper condition
No matter how durable and highly efficient your microwave is, the thermostat is still prone to get damaged or cracked. Therefore, if you are dealing with a microwave whose fan refuses to turn off, don’t forget to check the thermostat.
If the thermostat does not conduct continuity, you should get it replaced immediately. While looking for a new thermostat, keep the model of the microwave in mind and search for a compatible thermostat model.
Inspect the grease filter
The grease filter can be found at the bottom of the microwave. To inspect it, first, take it out. Now follow the steps mentioned below:
- Use running water and soap or detergent to clean the filter.
- See if there’s an accumulation of dirt and debris inside the filter. Sometimes, the dirt is so stubborn that it refuses to come out. In such cases, we advise buying a new grease filter.
- If you are using a microwave for quite some time, you must know that cleaning the filters regularly is a part of maintaining the microwave. Sometimes, that’s the only thing that ensures a microwave’s proper functioning.
Call the official helpline
If nothing of the above-mentioned methods worked out, you ought to inform a professional. We advise homeowners to let professionals handle electric appliances.
If you couldn’t reach out to a professional or they are taking time to come, you must always switch off the power supply before taking any step.
Homeowners should proceed to work on electric appliances only when they have the necessary equipment and required skills. Otherwise, it’s always safe and advisable to call a licensed technician.
Also, keep in mind that there are various reasons that can prevent your microwave fan from turning off. Some causes occur frequently while some occur rarely. For instance, the thermostat is most prone to failure while the control board is quite unlikely to go bad. Nevertheless, you must take good care of your machine and clean its various components from time to time, especially the filters.
If you haven’t used a microwave before and you don’t know how to maintain it, refer to the manual or contact any professional in that regard.