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Reasons Why Your Microwave Not Heating

A microwave can have an issue where the internal light will be on, and the plate will spin, however, the food or drink doesn’t get heated. It can also not start when you put in the cook time, and press start. In this article, I will explain the reasons why a microwave is not heating.

As a general rule, the temperature is set too low, your microwave is in demo mode, the control/child lock is on, the door is not completely closed, there is an error code on the LCD display, or one of the internal components has failed such as the diode, or magnetron.

Some of the reasons why a microwave does not heat can be fixed yourself, whereas, repairing components should not be done yourself unless you’re a qualified technician. Below, I will explain steps that can be taken to fix your microwave when it is not heating, and all the reasons why it’s happening.

Reasons Why Your Microwave Not Heating

A microwave has slightly complex components that are responsible for heating food and drink when it’s operating. However, oftentimes, there can be something simple that causes your microwave to not heat at all. Below, are the reasons why a microwave is not heating.

In general, your microwave is in demo mode, the temperature is set too low, the child/control lock is on, the door is partially open, or one of the components has failed such as a magnetron on diode. If a component has failed there can be an error code showing on the LCD display.

Demo mode is the most common cause because it gives the appearance that the microwave is on, but the heating function is disabled. It will allow you to set a cook time, and make it operate but won’t actually heat the food.

Here are the things you should check when you microwave is not heating. I’ve ordered from the most likely to fix the issue, and the easiest things to check first.

1. It’s in demo mode

Many microwave brands have what is called demo mode. Such as, Whirlpool, and GE. This is a mode that a microwave will be set to when it’s on display in a store.

When a microwave is in demo mode all the controls light up. But, it won’t heat. This mode is used to prevent someone from accidentally running the microwave on display in a store with no food in it, which can damage the microwave.

To take it out of demo mode refer to the owners manual for your make and model of microwave. Typically, it is easiest to get the online version of your owners manual, and then use the search feature by pressing ‘Ctrl + F’, to search for ‘demo’.

If nothing comes up then your microwave doesn’t have demo mode and you should move on to the next step. But, if it does then use the instructions for how to take it in and out of demo mode in your owner’s manual to ensure it’s not in demo mode.

2. Temperature is set too low for the food

Most microwaves have a heat setting. It can be set to low, medium, or high. Or, it can be set to a number from 1 to 10.

It’s possible your microwave has been set to the lowest heat setting somehow. You should check what level it’s on, and it’s commonly called the power setting. If you can find this button on the control panel, turn it up to medium or low, or from 1 out of 10 to 5 out of 10.

When you can’t find the setting then refer to the owners manual for your specific make and model of microwave. You can almost always find an online version of the owners manual for all the different microwaves. Especially for big brands such as Whirlpool, or Maytag.

3. Control or child lock is on

Microwaves commonly have a control lock or child lock. If this lock is enabled when you press the start button or any buttons on the control panel nothing will happen. This step only applies if your microwave doesn’t start.

If the internal light in your microwave comes on, and the plate in the microwave rotates but it doesn’t heat then the control lock or child lock isn’t the issue, and you should move on to step 4 below. When your microwave won’t start, and you can’t press any of the buttons then it’s possible the control lock is on. One of the buttons on the control panel should have a lock icon.

The screen on your microwave can also have a lock icon. If you press and hold the button that has a lock icon on the control panel, it will turn the lock off. But, if that doesn’t work then it needs to be disabled using a different combination of buttons.

Refer to the owners manual for your specific make and mode of microwave if you can’t turn the control/child lock off. Or, are unsure whether it’s on or not.

4. Door is not completely closed

If your microwave will not start when you press the start button, then a common reason why is the door is not closed completely. The internal computer on a microwave has a sensor that registers that the door is closed. If the door is pressed closed but hasn’t clicked closed then it won’t start.

A good indication this is the issue is the internal light will stay on even though the door looks closed. To fix it, open the microwave door, and close it again, pressing firmly. If the internal light stays even though you’ve pressed the door firmly closed, then the door latch may be faulty.

In other cases the internal computer may need to be restarted. You can restart your microwave by unplugging it at the wall for about 30 seconds. Then, plug it back in again.

Copyright protected content owner: ReadyToDIY.com and was initially posted on November 16, 2022.

If you suspect the door latch is faulty, then it’s strongly recommended to not repair it yourself unless you are a qualified repair technician. The reason is microwaves have very large amounts of electricity that flow through them. And if you make a minor mistake it can be very dangerous.

To have the door latch repaired contact your microwave manufacturer. It may also be covered under warranty. And your microwave manufacturer can advise you if this is the case.

5. Error code on the display

If there is fault with one of the internal components then the LCD display can have an error code. A list of error codes is commonly provided in the owner’s manual. Refer to the paper version of your owners manual.

Or, download an online version from your microwave manufacturer. If the owners manual does not provide a list of the error codes and what they mean, then it means a repair technician will need to take a look at it. You should contact your microwave manufacturer. They can advise of the next steps to take.

6. The diode is faulty and needs to be repaired or replaced

Overall, do not attempt to do this repair yourself. Microwave manufacturers have stated that anyone who is not a qualified technician should not open a microwave, and tinker with any of the components on a microwave.

Copyright article owner is ReadyToDiy.com for this article. This post was first published on November 16, 2022.

Therefore, you should not attempt to see if the diode is the issue, or replace the diode yourself. Instead, you should contact your microwave manufacturer, or a qualified technician.

7. The magnetron needs to be repaired or replaced.

The same rules apply for a magnetron that apply to the diode, and you should not attempt to repair it yourself. Instead, have a qualified technician to identify what the issue is, and repair or replace any parts that are required.

Is It Recommended to Fix Your Microwave Not Heating?

Home appliances are not overly complicated to take apart for someone who is a little bit experienced working with simple electronics. But, some repairs are very complicated and difficult to do even for someone with experience working with other appliances. So, here’s a rundown of whether someone who is not a repair technician can fix a microwave that isn’t heating.

Overall, it’s not recommended to do any repairs on the internal or external components of your microwave. But, you can try various things to do with the settings and controls which can cause your microwave to not heat food or drinks. Below are steps that can be performed yourself.

Microwaves are different to other appliances because they require large amounts of power to operate. For this reason, they have a transformer inside that generates very large amounts of electricity. If a minor mistake is made when repairing your microwave it can be very dangerous.

All microwave manufacturers also do not recommend repairing any components yourself. And instead have a qualified technician do it. In many cases, the cost of repair can be the same as the cost of buying a brand new microwave.

It can also be covered by the manufacturer’s warranty. So, it’s a good idea to contact your microwave manufacturer if you try the steps above that can be done yourself.

In general, your microwave is accidentally set to demo mode, the temperature/power setting is set too low, the control lock is on, the door is not closed properly, there is an error code showing on the display, or one of the internal components has failed.

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ReadyToDIY is the owner of this article. This post was published on November 16, 2022.

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