While the average do-it-yourselfer can safely disassemble most household appliances by taking simple precautions like unplugging the product’s power cord or switching off the circuit breaker to prevent voltage from reaching the product, taking a microwave oven apart can be considerably more dangerous. Why is disassembling a microwave riskier than, say, a dishwasher? And are all microwave oven repairs equally hazardous? Read on.
Always put safety first when attempting a microwave repair
To prevent electrical shock, you should always unplug an appliance’s power cord, or shut off the power going to that appliance, before removing any panels or covers. The same is true for microwave ovens which use very high current to operate. In fact, the microwave’s diode converts the alternating current (AC) power output of the transformer to direct current (DC), doubling the voltage to nearly 5,000 volts. This high voltage powers the magnetron to heat the food or beverage placed in the microwave and, under no circumstance, do you want to become a conduit for that voltage. Okay, so you’ll be sure to unplug the power cord. Anything else? Yes, there is: high voltage capacitors used in microwaves may retain a charge even after the power cord has been unplugged. You may think you will avoid being shocked because you unplugged the microwave’s power cord minutes earlier, but if you come in contact with a charged capacitor, the risk for injury and even death is considerable. This is why it is recommended that only experienced professionals access and replace internal components.
Not all microwave repairs are equally hazardous
Note that the above recommendation concerns internal components, meaning parts that you would need to fully remove the appliance’s shroud or cover to reach. There are actually quite a few microwave oven repairs you can do that are less risky since the procedure to replace the defective part doesn’t require the cover being removed:
- Glass tray replacement
- Tray roller support replacement
- Turntable drive coupling replacement
- Turntable motor replacement
- Filter replacement
- Door handle, door frame, and door latch replacement
- Wave guide cover replacement
- Many light bulb replacements
Of course, be sure to unplug the power cord before attempting any of the above.
Discharging a high voltage capacitor
If you do need to remove the microwave’s cover to replace components like the transformer, magnetron, or power cord, you should always ensure the capacitor is discharged as soon as you’ve lifted the cover off. While most high voltage capacitors used in recent microwave models have a bleeder resistor in them that should automatically discharge the capacitor after voltage has been discontinued, you’ll have better peace of mind if you discharge the capacitor manually. You can do this by placing a screwdriver blade or needle-nose pliers across each set of capacitor terminals. The handle of the screwdriver or pliers should be insulated, and you should avoid touching the metal portion of the tool when the tool is in contact with the terminals. Once you’ve confirmed the capacitor is discharged, replacing an internal component will be less risky.
How can I remove the microwave cover?
To access the capacitor to discharge it, you will almost certainly need to remove the microwave oven cover. Of course, you were going to do that anyway to replace that internal component, right? On stand-alone models, this can be as straight-forward as unthreading the mounting screws securing the cover from the side, top, or rear of the appliance. However, if the microwave if mounted to the wall under a cabinet, you will need to completely uninstall the appliance in order to remove the cover. While this process can differ depending on the model, here are 23 typical steps you can follow to successfully uninstall and then reinstall the microwave:
- Unplug the appliance’s power cord.
- Remove the glass tray and support from the oven cavity.
- Have an assistant help you to support the microwave as you unthread the screws securing the top of the microwave to the cabinet.
- Carefully tilt the appliance down and pull the power cord through the hole in the cabinet.
- Lift the microwave off of the mounting plate and set it on sturdy surface so its resting on its rear panel.
- Unthread the screws securing the oven’s bottom panel.
- Disconnect or detach any turntable motor or light wires secured to the panel and set the panel aside.
- Set the microwave oven upright and support the front with a 2×4 piece of wood.
- Open the door and unthread the screws securing the venting.
- Fully remove the venting (you might be able to use a putty knife to make this easier).
- As applicable, unthread the screws on the side, top, and rear securing the cover to the frame.
- You may also need to unthread the screws to remove the blower cover or air damper.
- You should now be able to slide the microwave’s cover back to remove.
- Discharge the potentially stored electrical charge in the capacitor and replace that defective internal part with a new one.
- Reinstall the cover along with the blower cover or air damper, as necessary, rethreading all of the screws.
- Replace the venting and secure it with the screws.
- Tip the microwave back on its rear panel.
- Reinstall the bottom panel by first reconnecting/reattaching the turntable motor or light wires, then fully align the panel and secure it with the screws.
- Carefully reposition the microwave oven on the tabs of the mounting plate.
- Feed the power cord through the hole in the cabinet.
- Lift the appliance up and rethread the screws to secure the top of the microwave cover to the cabinet.
- Replace the turntable support and align the glass tray on the motor coupler.
- Plug the power cord back in and your microwave oven should be ready for use.
Use Repair Clinic to find the right parts for your microwave oven
Whether you need to replace an internal microwave component like the magnetron, capacitor, or transformer, or a part that is more easily accessible, such as a glass tray, turntable drive coupling, or wave guide cover, you’ll want to make sure you’re purchasing the specific part that works with your appliance. This is where Repair Clinic can be a big help. All you need to do is enter the full model number of your microwave in the Repair Clinic website search bar to find a complete list of compatible parts. You can then use the “Part Category” filter (“Blower Wheel & Fan Blade”, “Glass Tray, Coupler & Support Roller”) as well as the “Part Title” filter (“Blower Housing”, “Glass Tray Drive Coupling”, “Diode”) to identify the exact part you need. Repair Clinic carries original manufacturer parts that match the most popular microwave models including those built by GE, Samsung, Whirlpool, LG, Kenmore, Frigidaire, and Panasonic, but you’ll want to make sure you order the right part for your repair to be successful.