Microwave makes unusual noise

Microwaves are essentially a new invention, however in only half a century they became nearly omnipresent. Microwaves offer a simple and fast way of cooking a wide variety of meals. Of course, you cannot cook everything in your microwave, and yet this is the easiest and simplest way of warming up snacks. Unfortunately, similar to other appliances the microwave will sooner or later break. However, keep in mind that you do not always have to replace your appliance – sometimes a simple repair can be enough.

A lot of our customers consider the strange noise coming from their microwave being an ominous sign – and they are correct. Even though the repair can be simple and cheap, it is certainly a good idea to diagnose your appliances early. A faulty cooling fan – a cheap and easy-to-replace microwave part – may result in your microwave overheating and eventually lead to a damage of more valuable parts.

There are several components, which can be the source of an unusual source. Sometimes it is possible to locate the source manually (for example, if it comes from the turntable motor), but sometimes you may have to check several components, before you pinpoint the source of the noise.

Drive Motor Makes Noise

The drive motor is located at the bottom part of the microwave oven, right under the turntable. This electric motor is used to turn the glass tray in your microwave. Sometimes, the drive motor may produce a loud grinding noise – in this case it has to be replaced. You may have to read the use manual or your appliance schematics for more specific guidelines regarding disassembling your microwave. Make sure to unplug it before you start to do it, however! The motor is normally held in place by retaining screws and wires. In rare cases, the noise can be caused by worn out mechanical components, such as a drive coupler or a roller guide. Check these parts for the signs of wear or cracks and replace them if needed.

Magnetron Makes Noise

Another common source of the noise can be the microwave magnetron. It might be producing a loud buzzing or humming noise. Magnetron is a part of a high voltage circuit that heats the meals in the microwave. You can find more information about the principles of magnetron work here. To diagnose the magnetron – unplug your microwave, and make sure to discharge the high voltage capacitors. Make sure magnetron’s high voltage diode is working and test if the mounting bolts are tight. Check the diode’s continuity with the multimeter. Make sure to check the continuity in the opposite direction as well! The multimeter should show continuity in one direction. We would recommend you to set an appointment with a professional technician in case this diagnostics sounds too complex for you.

Cooling Fan Makes Noise

Sometimes the unusual noise can be coming from the cooling fan of your microwave. This fan cools the magnetron while it is in use and is normally located deeper inside the cabinet. Unplug your appliance and take off the cabinet. Examine the fan, make sure there is no significant wear or damaged blades. You may want to clean it as well in case it is covered in dust. Make sure there are no other objects which could come in contact with the blades while the fan is spinning. You may have to replace the cooling fan in case you determine it is the source of the noise and it has the signs of wear.