Microwave Trips the Breaker when Opening the Door

Updated Jun 27, 2022 11:12 PM

There are few things more frustrating than electrical appliances that trip your circuit breaker. Even the best microwave oven can suffer from technical failings from time to time, but a tripped circuit will stop your meal dead in its tracks. Read our guide, and we’ll walk you through the possible reasons your microwave trips the breaker when opening the door.

KEY TAKEAWAYS:

  • A microwave that trips your breaker when opening the door affects expensive and cheap microwaves.
  • A broken door latch stops the interlocking switches from connecting, which causes the breaker to trip.
  • Make sure your microwave is plugged into the correct circuit, though some circuits cannot support a microwave at all.

Why Your Microwave May Be Tripping the Breaker

If this happens to you, it is usually due to an internal safety switch that saves the microwave from more damage. So, while it is annoying, it’s a sign that at least a part of the microwave is working. Keep in mind that your particular issue may not be listed here, so read our guide for how to test a microwave if your problem persists.

Insider Tip

Before troubleshooting your microwave door, make sure you have a screwdriver, rubber gloves, and a multimeter.

Broken Door Latch

If your microwave door latch is broken, it will affect the door’s interlock switch. There are two interlock switches, the primary switch and the secondary interlock switch, usually located under the control panel. A malfunction in either of these may be detected by the circuit and trigger a breaker trip.

You can investigate a broken safety interlock switch by yourself with a screwdriver and a multimeter. If your continuity reading is off, you need a new latch. That said, make sure to unplug the microwave and let it discharge for 15 minutes before operating. Contact a professional technician if you cannot see the connection terminals.

Circuit Overload

Most microwaves use a crowbar switch to protect you and your appliance from overloads. The microwave’s internal parts are safe, but your breaker will be tripped. This happens when a microwave’s power rating is too high and the appliance is plugged into the wrong wall plug type.

A licensed electrician can help alleviate the issue, even with a range microwave oven. You can test this for yourself by trying other appliances in the same wall plug. If your breaker doesn’t trip, your issue might be the microwave. Check out our guide on testing a microwave transformer for other possible fixes.

Broken Turntable Motor

If you hear a loud noise while your microwave is running, your turntable motor is probably wearing out. Most of the time, moisture or runoff food is the culprit behind a broken turntable motor. Replacing a turntable motor is pretty difficult, so get a second opinion from a diagnostician before working on the microwave.

As always, save yourself from possible electric shock and contact a professional electrician if you are ever unsure about repairing your major appliance yourself.

Warning

Microwaves are dangerous to work on if you don’t know what you’re doing. Never hesitate to ask an appliance technician for help.

F.A.Q.S

Where is the monitor switch?

Your monitor switch is located under the oven microwave control board and connects when your microwave door shuts. A bad monitor switch is one of the most common microwave issues.


How do I stop my appliances from tripping the breaker?

Make sure your device’s amp circuit is operating correctly. If not, the excess electrical current will be passed through and trip the breaker. In addition, make sure your appliances link up to the circuits that can handle their wattage needs.


Is a microwave worth fixing?

If hiring a major appliance repair tech costs more than replacing the bad microwave, consider a replacement. That said, if the repair is less than half the initial cost, the microwave is worth repairing.



STAT: According to a US Department of Energy survey, 62% of Americans use an average microwave heating time of one to three minutes. (source)

Christen da Costa Avatar

Learn More About Microwaves