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Discussion Starter · #1 ·
I have read some posts similar to what I'm posting, but the one that I found that was almost exactly the same to my predicament was solved when the guy replaced the capacitor and not the compressor fan motor.
My compressor fan motor is bad on my outside unit, the seals dry rotted and the grease or oil is all gone. It is on/in a Miller/Nordyne split unit. The old motor is a GE 5KCP39FF, 1/4 HP, 825 RPM, 208-230 V. Needless to say, I couldn't find an exact replacement for the almost 20 year old air conditioning unit.
I found and have ordered the closest replacement motor that I could and it is a GE 5KCP39JFBA835, 1/4 HP, 825 RPM, 208-230 V. Grainger has these for $157, but I found a new one for $80, shipping included.
The old motor has only 3 wires and the new motor looks to have more from the picture, as I haven't actually received it yet. Also, the new motor calls for a different run capacitor then what is currently on my outside unit.
The capacitor on it now is a 35+5 mfd X 440 VAC, 3 head/prong, which I replaced new, just a couple of months ago. I guess it is a dual run capacitor as it runs the fan and compressor.
Although I'm fairy sure the new motor will work and is compatible as a replacement, I have concerns in regards to the wiring and the capacitor.
At Grainger's website, they state that this particular motor requires a 7.5 mfd 370 VAC run capacitor. I looked at the picture of it and it has only 2 prongs on top.
So, obviously, I need some help with knowing how to correctly wire the new motor and advice concerning the capacitor.
The old motor has ROT_CAP 5.00/370 on the sticker.
I'm not sure about the sticker on the new motor as I haven't got it yet and I haven't been able to find a good picture of the sticker to read that info.
Here is a link to the motor at Granger's site: hxxp://www.grainger.com/Grainger/GENERAL-ELECTRIC-Condenser-Fan-Motor-2PRA6?Pid=search
h52
Will I need to order the capacitor that Grainger recommends, or do I need to find a dual run capacitor that has the same specs as the one they recommend? Will the new capacitor work with the compressor and fan?
All help and advice will be appreciated!
Thanks
 

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just get 35/7.5 MFD 440V dual capacitor.

 
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Buying a seperate 7.5 will be cheaper and easier for you to wire. The 5 on the duel cap will not be used and the 2 brown wires on the new motor go to the new 7.5.
 

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Discussion Starter · #4 ·
Buying a seperate 7.5 will be cheaper and easier for you to wire. The 5 on the duel cap will not be used and the 2 brown wires on the new motor go to the new 7.5.
When you say "The 5 on the duel cap will not be used", what do you mean as I only see "Fan", "C", and "HERM" at the 3 prongs on the capacitor.
Here is a picture of the fan motor if that helps any. You can see some of the wires. My old fan motor has only 3 wires: orange, black and blue. The orange wire goes to relay contact, blue wire goes to "Fan" on the capacitor and the black wire goes to the control module.
I realize it's hard for me to ask which color wire goes where on the new motor without me actually having it in front of me!
As for the 2 brown wires, which wire for which prong? Or does it matter?
Sorry....but do I need to wait until I get the motor to ask which wire goes where? I know I'll have to cut the shaft to correct length...that part I can understand.
Thanks
 

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Discussion Starter · #5 ·
I need to order the correct capacitor for the new motor ASAP, so it can arrive about the same time as the new fan motor. It's hot and we only have one window unit to rely on to cool my entire home! If I order a separate 7.5 capacitor, which one do I order? A 7.5/370 V, not a 7.5/440---or is that strictly a dual run capacitor?
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to make your life simple buy the dual capacitor. The voltage can not be less .... if it's greater no problem.
 
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Order a 7.5/370 although you can use a 440 in a pinch. Upsizing is OK downsizing Verbotten. On the dual cap disregard the Fan terminal and only use Herm and C. Then hook the new cap between the 2 brown wires on the motor and mount it with perf strapping somewhere. Be VERY careful to check the rotation so it sucks air into the sides of the unit and shoots out the top. If going backwards simply switch the 2 brown wires on the new cap to the opposite terminals and check rotation again. Be VERY careful to check the 2 incoming power lines for the unit to ground individually to make sure the switch works and shuts off the power.
 

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On the 3 prong capacitor C is common,herm is the compressor side(35) and fan is the 5. Since the new motor takes a 7.5 instead of a 5 you'll use a seperate capacitor rated at 7.5 and not use the (fan 5) on the 3 prong one. The C and herm still hooked up like they are now on the existing capacitor. Both browns go to the new 7.5, one on each side. Get a 440.

That leaves you with 2 wires left on the old motor and 2 wires left on the new motor. Black to where the old black was and white to where the orange was.
 

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Discussion Starter · #9 ·
I like simple. Hopefully, after I get the motor and capacitor, all I'll need is help in the wiring it up. I'll post back when I get to that point.
Thanks for all advice and help.
 

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Discussion Starter · #10 ·
On the 3 prong capacitor C is common,herm is the compressor side(35) and fan is the 5. Since the new motor takes a 7.5 instead of a 5 you'll use a seperate capacitor rated at 7.5 and not use the (fan 5) on the 3 prong one. The C and herm still hooked up like they are now on the existing capacitor. Both browns go to the new 7.5, one on each side. Get a 440.

That leaves you with 2 wires left on the old motor and 2 wires left on the new motor. Black to where the old black was and white to where the orange was.
I think you covered the wiring part for me. Thanks guys! You all saved me at least a couple of bens for not having to pay the local geniuses to do it!
 

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Discussion Starter · #11 ·
Guys, there are so many different 7.5/440 capacitors. Will this one best suit my needs? hxxp://cgi.ebay.com/7-5-uf-MFD-mf-440-VAC-OVAL-Motor-Run-Capacitor-12931-/250792291499?pt=LH_DefaultDomain_0&hash=item3a6462acab
Thanks
 

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get it from graingers. at least that way it won't turn out to be a used/repackaged one from z-bay.
 
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