Judy for Model Number 721-67903 We have a Kenmore Elite microwave/convection oven. It is heating just fine, but has a humming noise, and reading other online remarks I did my own test. I shut the door with a cup of water and it boiled, and continued to hum. The humming stops when I open the door. I didn't get any heat when the microwave was unplugged.???
Answer Judy, With the unit heating just with the door closed and not being turned to on then the issue will either be a shorted neutral wire that is touching ground or the issue is a faulty control board. Read More... Answered by AppliancePartsPros.com | Tuesday, July 1, 2014