Makes a humming noise wont heat - Kenmore 62622 Microwave Oven

The problem is most likely the magnetron is defective and the humming is a typical symptom that supports this, there are two other parts that may be a factor, the high voltage capacitor and diode they work with the magnetron to generate the high voltage that heats the food.

If its making a humming noise, that means the diode is bad and should be replaced. Once replaced the microwave will begin to heat again.