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Discussion Starter · #1 ·
I'm having trouble with my A/C. The old condensor motor went after 11 years and could not find the exact OEM. Was matched up with an AO Smith 182A. Installed with separate capacitor and it worked fine for 4 days. This morning when it went to kick on the motor ran slow and stopped after a minute or two. I had an hvac repairman over a week ago and he told me to take the motor back because it wouldn't work the way he hooked it up(onto a universal capacitor) on the 5mfd side. It ran slow the way he hooked it up so I put the separate capacitor in and it ran fine. I don't know if it shorted out because I didn't tape it onto anything and it may have touched the cover. Any way the motor is running slow and then heats up and shuts down. I hook it up to the universal capacitor and it runs the same. Do I need the separate capacitor which worked excellent for a few days or what? If anybody could help I would greatly appreciate it.
 

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Discussion Starter · #3 ·
Don't know how to test

I'm new at doing this. I don't know how to test uF on caps or check for draw on motor.
 

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Sounds like you had a dual run capacitor, three terminals. One for FAN one for HERMETIC one COMMON. If he wired in a dedicated run capaicitor he would have to change the wiring,

Very possible he made a mistake because the motor will run for a time before it goes bad.
 

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Discussion Starter · #5 ·
Motor Mate

Technician put in a motor mate capacitor. The old one did have three terminals. This one has more. Three plugs go on the common in the center, the compressor is on the blue, and the fan on the 5mfd. Fan still does not pick up to faster rpm.
 

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That replacement motor has two capacitor leads with powered wires a L1 and L2 leads for a total of four leads total.
Your OEM motor has only three.

Very possible he miswired it.
 

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Discussion Starter · #7 ·
You are correct hvaclover

That is correct. When I got the new motor I wired it the way the technician told me and it ran slow. Then I used the 5mfd capacitor that came with the motor and it worked perfect for 4 days. The technician told me the solid brown wire went on the common and the brown with the stripe went on the 5mfd. That was my first try and it ran slow. When it ran slow I unhooked the common and striped wire and put them on the separate capacitor and it ran good for 4 days. Then it ran slow that way too.
 

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Both browns to the new run cap is correct. Where are the other two hooked up? Both should go to the load side of the contactor, not to the dual cap. There should only be one wire, probably smaller, from the contactor to the dual cap common terminal at this point. Nothing from the new motor should be connected to the old cap, it should only be running the compressor.

Somebody correct me if there are different scenarios out there, but that's how the couple of Fasco universals I've installed worked.
 

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Discussion Starter · #10 ·
I think I'm getting somewhere

Okay, the black wire is connected to the contactor. The white wire the technician hooked up to the common on the new cap. So I have both brown wires hooked up to the little cap that came with the motor, now all I have to do is find out where the white wire goes and I'll be in business.
 

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Okay, the black wire is connected to the contactor. The white wire the technician hooked up to the common on the new cap. So I have both brown wires hooked up to the little cap that came with the motor, now all I have to do is find out where the white wire goes and I'll be in business.
Where on the contactor is the black connected? First you need to identify supply and load sides. Supply side is where you see a black and a white, typical household type wire. On the load side you'll see two large wires, one black, the other usually red or yellow, going to the compressor. This is where you'll make your connections. Connect black to black, white to the red or yellow.
I'm betting since it ran for 4 days with the white on the common, that you've fried the dual cap. If the fan runs normally after wiring it properly, go ahead and replace that dual cap before the compressor side dies as well, if it hasn't already.
 

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Discussion Starter · #12 ·
Okay

Okay, the black is to the black on the load side. The tech had a yellow jumper wire going to the common on the dual cap. Then the white going to the common. I hooked the white to the yellow on the load side and it still runs slow and then stops. I am puzzled.
 

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Okay, the black is to the black on the load side. The tech had a yellow jumper wire going to the common on the dual cap. Then the white going to the common. I hooked the white to the yellow on the load side and it still runs slow and then stops. I am puzzled.
Ok, where's the other end of that "jumper"? If it comes from a relay on the contactor that's normal, it powers the cap. Is the motor excessively hot when it stops? If not, then the new run cap is probably bad. If you can, take something like a long screwdriver and try to give the fan blade a spin manually while it's turned on. If it starts up that way, the cap is bad, replace it with an identical one.
If that doesn't work, you've got bigger problems, probably fried motor windings. You'll need to have the motor tested by a tech, this time one who can read the wiring diagram on a motor.:whistling2:
 

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Discussion Starter · #14 ·
Thanks for the help

OK, I got it connected and the motor is working fine. Didn't feel any cold air coming out so I hooked the jumper wire to the cap and now the compressor is working too. Thanks alot for the help.:)
 
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