Most dryer motors operate on 115 Volt A/C; however some dryers, mostly outside the US, can operate on 220 Volts A/C. A complete explanation of motor fundamentals is beyond the scope of this forum. However, we will briefly describe how dryer motors work.

Like any other motor a dryer motor converts electromagnetic energy to mechanical energy to turn the dryer blower and the dryer drum. The best way for non-technical people to check a dryer motor is to inspect it. When a dryer motor fails it usually burns up the windings inside the motor. Looking inside the motor you can see if the windings are burned. There is an odor associated with burned windings. Dryer motor bearings also seize up due to friction and heat.

If your dryer motor is humming when you press the start switch you can be about 85% sure the motor needs to be replaced. That’s because for a dryer motor to hum when the start button is pushed the electrical circuit to the motor must be complete and most likely the motor windings, motor bearings or centrifugal switch contacts are damaged.