Originally Posted by shughey00
Yah I see that now on the schematic for the wiring. Might try just replacing that first...then the motor if that isn't it. Motor isn't bound up or feel any resistance so...we will see.
1. Make sure all power to rooftop unit is off (at circuit breaker)
2. At the capacitor, remove wire from terminal marked "fan"
3. Measure resistance between this wire and terminal marked "common" on capacitor.
4. If this resistance is infinite your motor run winding is open (bad), replace the motor.
5. If the resistance is some 10's to 100's of ohms, it's MOST likely a bad capacitor - change it.
It's far more common for the capacitor to fail than for the motor to fail. Good service practice calls for capacitor replacement anytime you change a motor. There's nothing to lose by trying the capacitor change first.