How to Test the Magnetron in a Microwave

The magnetron in your microwave oven converts an electrical current into electromagnetic waves and directs them at the food on the turntable. The electromagnetic waves cause water molecules in the food to rapidly vibrate and heat up through friction. When the magnetron isn't working, you will find your food comes out of the oven cold after the microwave chimes. The magnetron is easily tested without special tools or equipment.

Instructions

1. • 1

     Fill a mug with room temperature water from your kitchen sink.

   • 2

     Place the mug of water on the glass cooking plate inside the microwave.

   • 3

     Set the microwave on "High" for one minute and press "Start." You should hear the magnetron hum while it is working.

   • 4

     Remove the mug carefully from the oven by its handle. The magnetron is working properly if the water is hot or warm. Contact the manufacturer for repair or a replacement oven if the water is still cold.