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Benjamin Orr
May 4, 2008, 02:08 AM
Hi, I installed a new emerson condenser fan motor on a lennox unit and for you guys with a johnstone catalog it was the s88-502 and called for the g21-933 capacitor which is a 7.5 370 volt. They didn't have that capacitor in stock and gave me the g32-480 which is 50.0/7.5 440 volt. Is this OK? Is the mfd the major factor here? Also the new motor was a 4 wire instead of a 3 wire like the old motor and I capped the brown/white wire and ran the brown to the capacitor like it called for in a 3 wire run. The black wire and the white wire called to go to the loads on the contactor. It doesn't matter which side they go on does it? The condenser unit runs fine now but I want to be sure on things. Thanks for any replies, I appreciate it.

hvacservicetech_07
May 4, 2008, 08:01 AM
It should be fine, they gave you a dual capacitor, as long as the brown wire is hooked to the "fan" terminal on the cap. What do you have hooked to the "c" terminal on the cap?

aldematt57
May 4, 2008, 09:56 AM
Yep. You got a dual cap and simply used the fan cap portion of it.
Always check the wiring diagram and notes that accompany any unit you service and keep a chart that shows conductor ratings in your truck.;)

Benjamin Orr
May 4, 2008, 10:58 AM
It should be fine, they gave you a dual capacitor, as long as the brown wire is hooked to the "fan" terminal on the cap. What do you have hooked to the "c" terminal on the cap?

I kept the same wire that was connected to the "c" that was on the old capacitor and the herm, compressor wire also put the same wire back. Is this run capacitor just for the fan or is the correct size needed for the respective compressor? What is the difference between a dual and a regular cap? An extra terminal? The old cap had the same connections. Thanks for the replies

T-Top
May 4, 2008, 02:33 PM
A dual capacitor is two in one, it will help with the compressor and fan motor in one unit. The regular as you say will only operate with one motor. You would need a separate run capacitor for the fan motor and compressor. Dual and single capacitors are common in all makes and models. Good question.