William D Dumfries , VA April 30, 2019 Appliance: Model WE21H720 Microwave stopped heating when magnetron failed, diagnosed by youtube video for loud humming sound Removed and replaced old magnetron and diode with exact replacement parts. Hardest part was so many screws in the microwave cover and lifting microwave back into position over the stove. Caution required when working around capacitor. See YouTube procedure. 4 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: 1-2 hours