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Old motor has 3 wires, new motor has 4 wires, WTF?


You always want to save a few bucks in these tough times right? Don't want to spend a fortune replacing the motor with the exactamundo. So you bought a generic motor with the same hp, speed, and amp rating. You get home and BOOM the thang has more wires than your old one. Do not panic. The new motor has several ways to connect common. The HVAC shop should sell you a new capacitor. Your old cap may not work on the new motor because it may not be rated the same, the 2 brown wires go to that capacitor. TIP: You need to secure the new capacitor where it won't short against anything, tape it up good. So that leaves 2 wires now instead of  3 you originally had, black and white. You connect black to black where it always went on the contactor and you connect the white one to the common. There may be some more wires that have to do with direction but that is easily explained on the motor. The HVAC guy will get it going in the right direction before you leave the shop if you bring the blade in. Your old motor had 3 wires.
 FYI: The old capacitor has 3 connections, HERM (hermetically sealed compressor), C (common), and F (fan).  The old motor had a white wire (or purple) that went to the old capacitor marked C (for common), the black wire to the contactor (for hot) and the brown wire to the F on the old cap. The new motor can be set up that way also if you prefer to do it that way. Providing the old cap is rated the same for the new motor you can attach the plain brown wire with a clip on it where the brown wire went on the old cap marked F. The other brown wire with white stripe and a clip on it would go to C on the old cap (for common) The black wire goes where the black went on the contactor. The remaining white wire would be taped off and not needed but it would be live so it needs to be taped off and out of the way. Got it? LOL


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