How do you wire a new Heat pump outside fan motor that has two wires when the old one has three?

Question

I just bought a emerson replacement fan motor for my outside heat pump unit. When I pulled it out of the box it only had a white wire and black wire. The old motor has a black, brown and purple wire. The Heat pump is old and I can not afford a new one just yet. How do I wire the new motor to the old heat pump when there is 3 wires and the new one only has two? The wiring diagram is saying to use the brown with white stripe for three wire hook up but if I do that how will I hook up the capacitor for the new motor? Can anyone help?
And getting a new heat pump is not the answer either for the ones who just wants to get points.

Thanks
Chad

There is a grounding wire on both motors and they are attached to the fan casing.

Answer 1

Check your paperwork! Your new moter may have a capacitor built in. You should find this info in your paperwork. If it has one built in than both leads are hot for 220v

Answer 2

Is the new motor the same voltage as the old? Perhaps the new is 120V and the old is 240V?

You could put a volt meter across the wires from the unit and turn it on and see what is going on.

Answer 3

One of the original wires was a ground wire.
The new fan should have a screw to attach a ground wire.
You will need to use a bare copper wire, attached from the casing of the fan to the existing ground wire.

Answer 4

The new motor might have a built-in capacitor?