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View Full Version : Roof top A.C. fan not working correctly


bomberbob
Jul 23, 2013, 04:47 AM
I have a York 12 ton AC unit on roof top with 3 condensers in it,1 condenser with 1 fan above it and 2 condensers with one fan above them.I had to replace fan above condenser 2 and 3 with new 3 wire fan motor and appropriate capacitor, original fan had 4 wires! I put black wire on contactor#2 and brown with white stripe to one side of capacitor and other brown to other side of cap.also have yellow wire from cap to contactor#2. Unit work for apprx 10 minutes than fan # 2 slows down and then contactor# 2 opens. Could really use help on this one!! Thankx in advance

Joshdta
Jul 23, 2013, 04:25 PM
Was the motor exact hp and rpm? Most 220 volt motors have 5 wires where are you get the other leg from threw the capacitor?

bomberbob
Jul 24, 2013, 06:11 AM
Sorry little bad info from my maintenance guy we have a 208 3 phase roof top unit and I checked wiring myself and found fan motor has 4 wires! Black went to phase 1 on contactor,white to phase 2 on cont. brown/white stripe to capacitor and solid brown to other side of cap. h.p.and rpm match also.The capacitor is a dual run and voltage and micro f match motor.Hope new info can shed some light on problem