I've got a Rheem Furnace which has the blower in it. The blower is also hooked up to a Trane AC unit. The blower does not come on but I hear a buzzing noise coming from either the transformer, or relay. I figured it was either the relay or capacitor and replaced them both for about $25. The motor still does not come on. The relay is getting an input of 24-25 VAC.
I've got 5 wires coming out of the relay. Small red and white on the top which is the input (25VAC). Two larger wires Red and Blue coming out of the middle and 1 small blue wire coming out of the bottom.
The fan motor does spin freely. Where do I go from here?

I would like to make sure the motor is bad, is there anyway I can check this?
I also notice a contactor in the circuit.How do I check this?
Is there anything else I should be checking before I go off and replace the motor?
Thanks for your help.

While it is buzzing... touch the motor and see if it is hot... if it is hot than the motor is burnt out. Another thing to check is for a start or run capacitor hooked up to the blower... if it is dead than the blower will hum because it isn't getting enough power to the blower to get it going.

If you try to turn the blower with the power off and id is hard to turn then you have bad bearings. Now depending on whether you have a direct drive or a belt driven blower wheel will determine what you have to replace. Direct drive units have the bearings in the motor and most times it is cheaper and less hassel to buy a new motor than to have to old one repaired.

Thanks for your help. The motor (direct drive) was bad. I replaced it cost about $70 and its working fine. The motor was getting hot and the voltage across the motor was about 100V.