How do I test if my blower motor is bad?

Testing whether a residential indoor air handler blower motor is bad involves performing a series of electrical and mechanical checks using a digital multimeter. First, turn off the electrical power to the air handler at your home's main circuit breaker panel for safety, and remove the service access panel. Inspect the blower motor for visual signs of failure, such as a burnt electrical odor, scorched wiring insulation, or a heavily cracked motor housing. Next, manually spin the blower wheel by hand; if the wheel feels stiff, binds up, or grinds heavily, the motor bearings have seized. Using a digital multimeter set to ohms, test the motor windings for continuity and check for shorts to ground against the motor casing. You can also test the run capacitor to ensure it is not dead. You can verify that the blower motor is bad when confirmed power reaches the unit, but the motor refuses to spin or fails electrical winding tests.