The microwave oven suddenly does not heat. Power supply problems, door switch problems, fuse problems, and faulty parts are as follows:

1. Power supply problem: Check whether the microwave oven is plugged in and whether the power supply is normal. powered by.

2. Door switch problem: The door switch of the microwave oven is damaged or does not work properly, causing the microwave oven to be unable to start the heating function. You can check whether the door switch is intact and can be closed normally.

3. Fuse problem: There is a fuse inside the microwave oven. When the microwave oven overheats, it will automatically disconnect the power to protect the microwave oven from damage. If the fuse is disconnected, the microwave oven will not be able to heat food. You can check whether the fuse is normal.

4. Faulty parts: The internal parts of the microwave oven are damaged or aged, such as magnetrons, high-voltage transformers, etc. These faulty parts will cause the microwave oven to be unable to generate enough microwave energy to heat food.

5. The principle of heating food in a microwave oven is based on microwave radiation. The microwave oven contains a microwave generator, a waveguide, a reflector and a heating cavity. When the microwave oven is started, the microwave generator generates high-frequency microwave signals, which are transmitted to the heating cavity through the waveguide. The inside of the heating chamber is usually covered with a special coating that reflects microwaves rather than absorbs them.