Most Repairs Require:
- A flat-edge screwdriver
- A Phillips-head screwdriver
- A multimeter
- A replacement part
due to the very high electric potential and high current that microwave ovens require, the gamble of electrocution is high when repairing the appliance. The high voltage capacitor inside the microwave can store a lethal amount of electricity, even after the microwave has been disconnected from the power for several months. To safely access electrical components in the microwave, the capacitor must be discharged .
The capacitor can be discharged by touching both the positive and negative terminals of the capacitor with a metallic element screwdriver blade. Precautions must be taken to insulate yourself against electrocution. A screwdriver with a rubber handle, or needle-nose pliers with condom handles, could besides be used to discharge the capacitor. If you are diffident, you should leave it to a discipline professional .
1. Blown Main Fuse
The most coarse cause of a microwave not working is that the chief fuse has blown. The fuse will frequently blow because of a ability fluctuation or a bad door trade. It can besides blow because another contribution, like the magnetron or capacitor, is defective. It is important to find the cause of the fellate fuse, as a newly blend will probable blow again if the issue is not resolved. apart from the condom concerns, microwave fuses are relatively easy to install and inexpensive to replace.
Microwave fuses can be tested with a multimeter for continuity ( a continuous electric path present in the fuse ). If the fuse tests negative for continuity, it will need to be replaced. When replacing microwave fuses, ensure that the surrogate fuse matches the specifications of the old fuse, as the wrong fuse will blow again angstrom soon as you try to use the microwave .
The main fuse is normally located near the power cord but can depend on the induce and model of the microwave. Refer to your microwave ’ s manual and/or wiring diagram for the placement of the fuse. Make surely to follow the above guard warning before accessing the microwave .
To test and replace the fuse:
- Disconnect the microwave from the power source.
- Remove the relevant access panel. Depending on the make and model, you may need to unscrew the control panel or microwave frame. If you need to disconnect any wires; note how the wires are connected so that they can be reconnected when reassembling the microwave.
- Unscrew or unclip the fuse and remove it from the microwave.
- Test the fuse with a multimeter for continuity.
- If defective, replace the fuse with a new one that matches the fuse you removed.
- Reassemble the microwave and restore the power.
2. Defective Door Switch
For guard, the microwave will not operate if the door is not closed. Microwave ovens typically have three or four door switches that cut off the power to the microwave if the door is not closed properly. sometimes, a door switch will fail, normally due to wear and tear or because it is stuck. If a door switch has failed, the microwave will not work .
Door switches can be tested with a multimeter for continuity to determine if they need to be replaced. Make certain to follow the safety warning above before accessing the microwave .
To check and replace a door switch:
- Unplug the microwave from the power source.
- Unscrew the grille and/or control panel.
- Remove the switch assembly mounting screws.
- Depress the release tab and the actuator to the switch you are replacing.
- Disconnect the wire connector and remove the switch from the microwave.
- Test the door switch with a multimeter for continuity.
- Replace a defective door switch.
3. Other Fuses
Microwaves besides contain thermal fuses, cavity fuses, and thermoprotectors, which are designed to cut off the office to the microwave if the appliance overheats. Like the main fuse, these fuses will need to be replaced if they have blown. It is besides important to resolve the return that caused the blend to blow. A multimeter can again be used to test the fuses for continuity. Follow the independent fuse instructions above to access, test, and replace early microwave fuses .
4. Door Latch Assembly
Like the door switch, if the microwave door is failing to latch, the microwave may not start. Most microwaves have two plastic hooks that engage with the doorway switch to close the microwave door and signal that the microwave is dependable to begin heating. It is besides common for the door latch assembly to feature a spring to keep tension on the door latch. If the spring is loose and not providing tension, the microwave door will probably fail to close by rights, and the microwave will not work.
Read more: Heat transfer in microwave heating
To check and replace the door latch:
- To be safe, disconnect the power to the microwave.
- Open the microwave door and remove the plastic trim panel that runs around the inner lip of the microwave window and over the door latch assembly. On most microwaves, the trim panel is held on by clips. The panel can be unclipped by using a flat-edge screwdriver to get behind the panel and wedge it off. Be careful not to break the plastic. If you can access the door latch assembly, you may not need to take the whole panel off.
- Check the door latch assembly for signs of wear, cracking, discoloration, or damage. If there is damage to the door latch assembly, it will likely need to be replaced to get the microwave working again.
- Check the door latch assembly spring to see if a tab that the spring hooks onto has broken, causing the spring to lose tension. If a tab has broken, see if there is another tab that the spring can be hooked onto to restore tension in the spring. If you are unable to reset the spring, the door latch assembly will need to be replaced.
- If you need to remove the door latch assembly, take note of how the assembly is secured to the microwave door so that it is easier to replace it.
5. Main Control Board
If the above causes have not caused the microwave to stop working, you may have a bad chief control board. however, this topic is rare. dominance boards can be unmanageable to test but can be examined for corrosion and free wires. If you suspect the control board is causing the consequence, you will probably need to contact a coach professional, and the control board will likely need to be replaced .
Read more: Heat transfer in microwave heating