My Microwave Is Sparking | What To Do?

If your microwave starts sparking, switch it off and unplug it immediately. It’s possible that there may have been previously unseen incidents of sparking before, and there may be burn spots, so it’s important to get it fixed otherwise a fire might break out.

Check for Metal

Check the microwave for metal fragments that may have crept in – wire wool fragments from cleaning, for example, or even foil from a previous microwave cooking faux pas.

Check inside the microwave for damage

Damage to the internal walls of the microwave such as paint chipping can expose the metal and cause your microwave to spark.  Paint over these areas with microwave-safe paint.

Check the waveguide

Check the waveguide cover for any signs of damage damaged and replace it if necessary.  The waveguide is located inside the microwave and is a rectangular component, feels like a piece of card, that sits in front of the magnetron.

Microwave Safe Containers and Bowls

Alwasy ensure that the bowls and containers that you use for cooking in the microwave are classified as 'microwave safe'.  Never use metal bowls or utensils inside your microwave.

Faulty Magnetron

If sparking is coming from inside one of the side walls of the microwave, the magnetron is likely to be faulty.  Replacing the magnetron should only be carried out by a qualified repair engineer.

Other Causes

Many more minor problems can also cause microwave sparking, for instance burnt-on food or food prepared in certain specific ways (the classic example is a grape cut almost in half, but there are many ways you can create a hazard with food in a microwave). If this is the source of the problem, you might not need to take any action at all.