One of the most frustrating appliance issues is when your microwave won’t heat. In this blog post, we’ll be outlining some of the most common causes for this baffling problem.

Before we continue, please be warned: microwave ovens can hold deadly amounts of electricity in the high voltage capacitor, even after they have been unplugged. To put it in perspective, a microwave needs about 120 volts to operate, while anything above 30 volts is considered unsafe for humans. As such, microwaves are easily one of the most dangerous household appliances to repair. Do not repair or troubleshoot a microwave yourself, as this is best left for a licensed technician.

Without further ado, here are the three most common causes of microwaves failing to heat. 80 or 90% of the time, a microwave that runs but doesn’t heat will be a result of one of these issues.

    The diode has burnt out. The diode in your microwave works with the capacitor to double the voltage, which is necessary to power the magnetron, which then heats the food. As such, if the diode burns out, your microwave will be powered but not have enough power to heat your food. The good news is that a burnt diode can be easy to spot, as it may be visibly burnt, making this an easy problem for a technician to fix.
    A door switch is malfunctioning. Did you know that the average microwave has three or four door switches? These switches activate when you close the door to ensure that the door is completely closed. It’s a safety mechanism to ensure that the microwave does not generate any harmful radiation while the door is open. When a microwave is working properly, it will only begin heating after these door switches are triggered in a certain sequence. If one of these switches isn’t working, the microwave will not heat.
    The magnetron has burnt out. The magnetron is a critical feature of the microwave heating function. Unfortunately, if the magnetron has burnt out, it can mean an expensive repair. If the magnetron is not drawing energy, it also means the high voltage capacitor could remain charged for a long time, which makes the microwave especially dangerous.

If your microwave isn’t heating, it’s worth calling a licensed repair technician. While microwaves are perfectly safe for everyday use, replacing or testing electrical components should only be done by a licensed professional.

Thankfully, our technicians have exhaustive experience with safely repairing microwave ovens and are standing by to answer your call. Fix your microwave today!