Microwave is Sparking or Arcing - Microwave Not Working - Appliance tip of the week

Microwave is Sparking or Arcing

The 3 most common part(s) or condition(s) which cause the symptom Microwave is sparking or arcing are listed below starting with the most likely.

Waveguide Cover

If the microwave is sparking or arcing the waveguide cover might be damaged and shorting out. Try removing the waveguide cover and see if the problem goes away. If there are any damaged spots in the microwave ceiling or sidewalls, repair them and paint them with microwave oven paint. Replace the waveguide cover if it is burnt or if it will not stay in place.

Paint

If the microwave is sparking or arcing on the side walls the paint might have chipped causing pitting in the metal oven wall. Use microwave safe paint to touch up any bare metal spots.

Rack Support

If the microwave is sparking or arcing near one of the rack supports, remove the support, repaint any bare metal, install a new support.

Microwave Not Working

The 4 most common part(s) or condition(s) which cause the symptom Microwave not working are listed below starting with the most likely.

Line Fuse

Every microwave oven has a line fuse. This fuse is designed to blow if too much current is drawn through the microwave circuitry. The fuse can be replaced, but the underlying issue should still be investigated and resolved. Otherwise the new fuse will blow also.

Main Control Board

If the microwave is not working the main control board may be defective. This is not common. When a microwave stops working the problem is usually the line fuse or within the high voltage circuit; either the high voltage capacitor, diode, transformer or magnetron.

Thermal Fuse

If the microwave is not working the thermal fuse may have blown. It can be tested for continuity.

Thermoprotector

If the microwave is not working the thermoprotector may have tripped. This is a safety device to prevent the microwave from overheating. It can be tested for continuity to see if it's blown.

Microwave is Sparking or Arcing - Microwave Not Working - Appliance tip of the week-waveguide-cover-40qbp1012-00560510-jpg LINK> Universal waveguide material, cut to fit, 10 inches by 12 inches

Microwave is Sparking or Arcing - Microwave Not Working - Appliance tip of the week-glass-tray-1b71961e-01530331-jpg LINK> Glass tray

Microwave is Sparking or Arcing - Microwave Not Working - Appliance tip of the week-door-switch-3b73362f-01053786-jpg LINK> Micro switch, normally open

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