Wiring in Condenser Fan Motors – Short #199

In this short episode, Bryan talks about wiring in condenser fan motors, including aftermarket motor considerations and the different wire configurations.

When condensing fan motors fail, we need to know what to use to replace them. We often use PSC motors, though in cases when we replace a motor with an ECM, we still need to match the horsepower despite the increased flexibility. The motors we typically keep on our truck are 1/3 or 1/6 HP motors.

Frame size (diameter) and depth also come into play; you may encounter a 42-frame motor or a 48-frame motor. You can't replace an 825 RPM motor with a 1075 RPM one because the poles are different (6-pole vs. 8-pole). Single-phase 208/230v will be the most common motors in residential systems, and the phase and voltage must match. You should also know how to reverse a motor if it is reversible. The bearing type will have some tradeoffs; ball bearings last longer but are louder than sleeve bearings.

3-wire and 4-wire condensing fan motors are essentially the same; the white wire and brown-and-white wire are essentially the same, as there is a jumper inside the motor. You can connect a 4-wire condenser to both sides of the capacitor; in any case, follow the wiring diagram.

When mounting a motor, make sure the wires are strapped properly. Then, remember to unplug the correct weep ports (opposite side of the shaft) to allow condensate to drain out.

Have a question that you want us to answer on the podcast? Submit your questions at

Purchase your tickets or learn more about the 6th Annual HVACR Training Symposium at

Subscribe to our podcast on your iPhone or Android.

Subscribe to our YouTube channel.

Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.





To continue you need to agree to our terms.

The HVAC School site, podcast and tech tips
made possible by generous support from