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Can Microwave Oven Overheat and Shut Off? (Explained)

You perhaps have encountered many appliances regardless of home or cooking to overheat and shut down. Hence, microwave ovens fall in the category of a super essential cooking appliance for daily life, such overheating and shutting off can be a troublesome issue. 

Therefore, it’s very usual for you to want to know can microwave oven also overheat and shut off like other cooking appliances or not. Thence, to solve all your queries regarding this issue let’s read further and find out. 

Can Microwave Oven Overheat And Shut Off?

While heating the foods if the foods are left with no moisture to get heated, it can cause a microwave oven to overheat and shut off automatically to prevent further problems. Also, if you are cooking in a microwave oven for a long time or it has a faulty fan, it can overheat and shut down. 

It’s not impossible for a microwave to overheat and shut off either. And such overheating and sudden shutting off take place due to foods with no moisture.

A microwave oven warms or cooks foods by generating energy waves that target and agitate the water molecules which make the foods get heated up from inside out. 

But when there is no water is left in the foods that are being warmed up or cooked, it will cause the microwave to overheat and shut down automatically. So that the microwave oven can protect itself and prevent further mechanical failure.

Except, for this reason, a microwave oven also can get heated and shut off if it is being used for a prolonged time for cooling or warming food as the temperature will get too higher. 

Besides, if a microwave oven has a faulty fan, it tends to make the appliance overheat and turn off on its own.

Why Does My Microwave Overheat And Shut Off?

Hence by now, you already know that foods with no moisture at all are mainly responsible for overheating a microwave oven and cause it to shut off suddenly. 

But it’s not the only reason, therefore, the other possible reasons that can cause your microwave oven to overheat and shut off have been summarized below –

Microwave Fan Failure:

Every microwave oven comes with a fan that helps the microwave source to cool down while it radiates waves to warm/cook foods. 

When the microwave fan failure occurs, the oven loses its capability to run swiftly because the fan can’t control the temperature anymore. As a result, the oven quickly gets overheated and causes a sudden shutting off in the midst of cooking.

Overheated High Voltage Parts:

Microwave ovens include high voltage components inside the unit. So if the high voltage components get overheated, it makes the oven overheat too. 

And it leads the thermal cut-out function to be turned on to avoid more overheating, thence, the microwave oven shuts down on itself.

Long Cooking Period:

Using a microwave oven for a long time while cooking or warming foods is another main reason that can cause your microwave oven to overheat and shut off. 

As the warmth from steamed or warmed-up foods remains within the oven box, and it’s not the part that the temperature detector can detect. As a consequence, the microwave oven gets overheated and turn off.

Specific Temperature Is Crossed:

A microwave oven has its own particular temperature limit, if that temperature is crossed while using it, the oven will overheat and shut off automatically.

Also, if the microwave oven has a faulty clock and timer, it would cause overheating and shutting off suddenly.

Do Microwaves Shut Off When Overheated?

Microwave ovens do shut off when they are overheated.

The majority of the modern microwave ovens come with an automatic shut-off feature which gets activated as soon as the oven reaches its highest temperature and is overheated so that the safety of the oven and people is ensured.

The microwave ovens shut off, to prevent mechanical and electronic mishaps.

What Happens If The Microwave Overheats?

Typically, when the microwave overheats, it shuts off itself without warming at all. And if the microwave keeps getting overheated and shuts off, at one point, it will create bigger problems such as a mechanical or electrical fault. 

Sometimes the overheating can turn into an unwanted blow-up or fire risk but it’s very less likely to happen. Besides, the food you will be cooking or warming can get burnt as well.

What Do I Do After My Microwave Overheated And Shut Off?

If you don’t know what exactly you should do after your microwave oven gets overheated and shut off automatically, you might panic a lot.

Therefore, the ways you should follow after the microwave is overheated and has shut off have been precisely explained below.

Unplug The Microwave:

Unplugging your microwave oven from the main socket is the first and primary way you can follow after noticing your microwave oven went off due to overheating.

After unplugging the microwave oven, keep the oven’s door open for about 15-20 minutes at least, and let the oven cool down for a while. Then set the clock and timer and plug the oven back in. It should begin to functioning again.

Fix The Fan:

If the fan failure is the main reason that has caused your microwave oven to get overheated and shut off then fixing the fan is the only way you should pursue it.

A fan failure can occur due to a dirty grease filter, clogged charcoal filter, faulty damper, or faulty fan motor. So in the case of a dirty clogged charcoal filter, replace it. And in case of a dirty grease filter, clean it with water and soap or replace it if it’s damaged.

If the damper assembly is causing a fan failure, you need to replace it as well.

When the fan motor is causing the fan failure, you can do two things. First, check the motor and rotate it manually, if it works then test it by using a multi-meter. But if the motor doesn’t turn, replace it to fix the fan.

Replace Magnetron:

First, you got to inspect whether or not you are receiving voltage on the primary of the transformer. If so, then most likely the magnetron went open circuit. If the root cause is an open circuit magnetron, you must replace it with a new cap and HV diode. 

And the problem is most likely to be solved.

How To Fix An Overheated Microwave?

Among all of the reasons behind an overheated microwave, a faulty fan is one of the main reasons, and most of the time it occurs due to a faulty fan motor. So to help you fix a faulty fan motor to stop overheating the microwave here the step-by-step instructions are explained

Unplug The Microwave Oven:

First, stay unplugging the microwave oven from your wall socket to begin the process of fixing a faulty fan motor.

Remove The Fan Motor:

The next step is removing the fan motor from the microwave. Generally, a fan motor is placed close to the top part, the backside of a microwave oven. Uncover the portion where the fan is placed and remove the motor.

Rotate The Motor Manually:

After removing the fan motor, try to rotate the fan motor manually. If the fan turns, use a multi-meter to test the fan.

Test With Multi-Meter:

In this step, set the multi-meter to Rx1 and sense the fan motor’s terminals by using the probes and check its continuity. If you get a reading of 0, know that there’s still continuity and it will work, so you don’t have to change it and put it back.

Replace The Fan Motor:

If the fan doesn’t spin in step 3, you got to replace it with a new motor. Therefore, remove the ruined fan motor and replace it with a new one. And the fan should work properly after putting it back inside the oven. Also, your microwave oven will not overheat as well.

What Happens If You Run A Microwave For Too Long?

If you run a microwave for too long, the microwave oven will get overheat, and as a consequence, the oven will shut off eventually.

Also, if you run an empty microwave for a long time, it will damage the magnetron inside and your microwave oven will not heat food properly.

How Long Does It Take A Microwave To Cool Down?

A microwave usually takes around 14-15 minutes to cool down after it’s been plugged off. Sometimes it may take a little longer time to cool down completely, do wait patiently until it cools off.

Final Thoughts

It’s unlikely that a microwave oven will overheat and shut off on its own but it can happen. And it mainly happens when the microwave can’t target any moisture on food. Sometimes, the fan failure and over time using of the microwave oven is also responsible for an overheated oven and shut off.