Furnace Blower Motor fan hums but wont start until I turn it by hand, then it runs fine. What should I check?
Before I would check for any of the potential electrical issues I would try lubricating the motor shaft. Shut off the power to the furnace. Gain access to the fan and motor. Spray a small amount of lubricant (slick50,chain lube, etc) almost any light oil will work, on the shaft where it exits the motor. Some models may even have been equipped with a small oil port from the factory. You may have access to the opposite end depending on the design. Spin the fan by hand a few times. Apply a small amount of oil again. Wipe off any excess, reassemble and see if the fan starts.