If the microwave has stopped heating food, there are several ways to identify and fix the problem. Sometimes this is very easy to do, you just need to reset the GFCI fuse. Malfunctions can also be associated with a rotating mechanism, a door switch or a fuse. What will be the solution to the problem depends on what you see when you try to bring the microwave into operation.
The most common causes of microwave oven failure
If you are unable to start the appliance in the normal way, try resetting the GFCI switch that is built directly into the outlet. First, check if the microwave is connected to the mains and if the GFCI has tripped, which interrupts the power supply in case of an emergency.
The last step in this step is to check the electrical system in the switchboard. Perhaps the toggle switch has worked, then the light will go out in the whole house or in part of it. This happens with an increased load on the wiring or a sharp power surge. Bring the electric machine into working condition, and the microwave will work as usual.
If the problem is not related to the electrician, it is worth looking for the cause of the problem in the microwave itself.
Thermal fuse
Household appliances stop working normally when this part burns out. The main symptom of a thermal fuse failure is that the microwave turns on, but does not spin or heat.
The thermal fuse is an element of the security system. The part is triggered when the temperature inside the microwave reaches a certain upper limit. Then the fuse gives a “stop” signal for heating.
You can check the quality of the part using a multimeter. If the thermal fuse is blown, it will not be able to conduct current, which means it will have to be replaced with a new one.
Slammed door
The second reason why the microwave stops working is that you slammed the appliance door, and now the appliance does not turn on. This happens due to a blown fuse. To make sure it’s the problem, use a multimeter and check for continuity. In the event of a breakdown, the only solution is to replace the fuse.
Problems with diode, capacitor, and magnetron
The microwave may even make the characteristic buzzing sounds that occur during its normal operation, but the food will still remain cold. In such a situation, it can be assumed that the power diode has broken, and you will probably have to replace it.
The main function of a power diode is to pass heat and block flow in opposite directions. If a part fails, the microwave cannot generate the energy needed to heat food.
The second reason for the lack of heat in the device is the breakdown of the high-voltage capacitor. The microwave continues to beep when you turn it on. The task of this part is to inject heat inside the device. If the capacitor breaks, the microwave cannot produce enough heat energy to function properly.
The last reason associated with the lack of heating is problems with the magnetron. This is the heart of the microwave, its main detail. If it does not oscillate as it should, there will be no heating. After diagnosing your microwave, you can assume that there is a problem with the magnetron, but only a professional in their field will cope with the task of replacing the part.
Door latch problem
This part of the locking mechanism is made of plastic hooks that tightly lock and instantly open the door when a special button is pressed. Over time, the springs in the locking mechanism can be stretched or damaged, and then the door will not fit well to the body. And when the door is not completely closed, the heating start sensor does not receive a signal to start work.
If the door latch is worn out, you will have to install a new part. To do this, follow these steps:
- unplug the microwave;
- remove the inner door panel;
- inspect the latch;
- if it breaks, replace it with a new one;
- connect the microwave to the mains;
- check the operability of the device.
Door switch problem
In this case, everything is in order with the locking mechanism, and it is the sensor that sends a signal to the magnetron that fails. Over time, the door switch wears out and ceases to fully fulfill its task, so the microwave heats up intermittently, and then completely breaks down.
The functionality of the sensor is checked with a multimeter. In the event of a malfunction, the part will have to be completely replaced.
The microwave turns on and off immediately
Have you observed such that when you turn on the device, it works for 2-3 seconds, and then it goes out? There are several reasons for this phenomenon:
- the door switch is out of order;
- the main control board is worn out and will soon stop working;
- broken touch panel (rarely happens);
- the high voltage transformer has stopped functioning;
- probably, the thermal sensor protecting from excessive heating has worked;
- the thermostat is out of order.
All parts through which electric current passes, check with a multimeter. If the circuit breaks in them, this means that they can no longer perform their functions and require replacement. The same situation is with the control board, most often this part cannot be repaired.
Turntable locked
The swivel mechanism stops rotating if there are problems with its parts. Your actions:
- Locate the drive sleeve connector. This is a plastic piece attached to the base of the microwave. Inspect it for breakage and cracks. The connector must be intact. If there is physical damage, replace the part.
- Inspect the turntable guide. She holds a dish on which you put a plate of food. It has the form of a round plastic stand or three plastic “beams”. Make sure that the guide lies in a horizontal plane, and align it if necessary. In the presence of mechanical damage, replacement is required.
- Inspect the dish (plate / baking sheet) on which your dishes with food are placed. It must fit perfectly on the guide and connector. If the dish moves, it will not rotate.
If all of the above elements are in order, and the carousel still does not spin, there is a risk that the motor that drives the structure has burned out. You will again need a multimeter.
Microwave sparks
This phenomenon occurs when a metal object or dish with a metal coating enters the chamber. The microwave begins to crackle violently, and sparks fly inside. In this case, the device itself will not turn off until the timer reaches zero. You need to manually turn off the microwave, wait a bit until it cools down, and only then open the door and get the source of sparks.
Try starting the microwave again. If sparks continue to fly, the cause may be splashes of grease or oil remaining on the walls. It is important to clean the device chamber in time so as not to expose yourself to unnecessary risk.
Also, sparking can be a sign of a problem with the rotating mechanism or the high-voltage diode.
When do you need the help of a master?
If you do not understand the device of a microwave oven at all, it is worth taking the device for repair to a specialized service center. It is especially dangerous to repair systems that involve electricity and wiring on your own.
And if the microwave oven is already more than 10-15 years old, you should think about buying new household appliances. Modern models are energy efficient and equipped with useful operating modes.