The microwave oven suddenly broke down!
Mechanically controlled microwave oven: mechanical timer and magnetron temperature limiter can be checked. Computer-controlled microwave oven: observe the safety tube of the computer board, and check the power transformer and magnetron temperature limit protector on the computer board. After troubleshooting, the safety tube tester can be replaced.
2. There is no response when the power is turned on, and the fuse is blown.
Check the door switch, microwave high voltage system (high voltage transformer, high voltage diode, magnetron and high voltage capacitor), fan motor and turntable motor. After troubleshooting, the safety tube tester can be replaced.
Check the high-voltage transformer mainly to observe whether the primary winding and high-voltage winding are burnt or not, and whether the insulating paint is burnt or not.
3. Burn the power fuse repeatedly
Check the door switch and high-voltage transformer first, and then check other devices in the microwave system, such as high-voltage diodes, high-voltage capacitors, bidirectional diodes, magnetrons, etc.
It can run, but the microwave oven is not heated.
Firstly, whether there is power supply on the primary side of high voltage transformer is measured, and then the maintenance range is determined according to the measurement results. If it is measured that there is no AC220V power supply in the primary of the high voltage transformer, the microwave oven is mechanically controlled, so check the timer and door switch; When the computer controls the microwave oven, check the door switch, computer board fire relay and drive transistor. If AC220V power supply is detected at the primary of the high voltage transformer, check the high voltage transformer, high voltage fuse, high voltage diode and protection diode.
If the microwave oven is not heated, the noise will increase or the vibration will be great. Focus on microwave systems, such as high-voltage diodes, high-voltage transformers, high-voltage capacitors, bidirectional diodes, magnetrons, etc.
6. Microwave heating is slow, and the firepower is obviously less than before. This kind of fault is usually the aging of magnetron, and a few are the poor contact of power control selector switch or power relay.
7. If the barbecue grill is not heated, check whether the barbecue grill has AC220V power supply. If the power supply is normal, replace the barbecue tube; If there is no power supply voltage, check the barbecue control circuit, such as barbecue temperature limit protector and barbecue switch. For computer-controlled microwave ovens, check the barbecue relay and drive transistor.
8. After starting the machine, the inner container is ignited. Under the condition of confirming that the user has never used metal utensils, check whether the mica sheet is burnt and whether the inner container is too wet.
9. Start or stop key failure
Generally found in computer-controlled microwave ovens, check the membrane switch.
10. There is a display when the computer microwave oven is powered on, but the door switch and the switch on the panel are not started.
1 1. Sometimes it doesn't start, sometimes it automatically switches functions, and the buzzer rings by mistake.
Measure the +5V, reset and clock oscillation pin voltages of CPU, and replace the crystal.
12. Tray does not work
Check the pallet synchronous motor and its power supply voltage when the shaft and track are normal.
13. The fan motor does not work.
Check the fan motor and power supply.
14. After opening the oven door, the motor of the oven panel still rotates.
Computer-controlled microwave oven, check the main relay and control transistor on the computer board; Mechanically control the microwave oven and check the oven door switch.
15. Without stopping the heating of the mechanical microwave oven, check whether the timing motor is damaged, whether the rotating shaft of the timing button adheres to the panel, and whether the power supply of the timing motor is normal.
Timer motors can be divided into AC220V and AC50V. If the fan motor is damaged, the timer motor will stall.