Swapping A/C capacitors
#1
04-21-20, 12:16 PM
Swapping A/C capacitors
I purchased a new AC capacitor for my compressor on eBay and tried to get the models numbers and specifications exact , but when it came in they're slightly different (see attached photos).
For one, the new one doesn't seem to be as long and two, there are only two terminals on the new one while the old one had three, even though the third one is unused.
Can I still replace the old one with the new?
Thanks!
For one, the new one doesn't seem to be as long and two, there are only two terminals on the new one while the old one had three, even though the third one is unused.
Can I still replace the old one with the new?
Thanks!
#2
04-21-20, 01:33 PM
Group Moderator
#4
04-21-20, 01:45 PM
Group Moderator
The rating is 55mfd at 440vAC on both caps.
I wouldn't have told him it was ok if the rating was wrong.
The old cap had a dual section for the fan that's not being used.
I wouldn't have told him it was ok if the rating was wrong.
The old cap had a dual section for the fan that's not being used.
#5
04-21-20, 01:49 PM
They're the same rating:
55 uf +6 - 6%, 440VAC, 50/60 Hz. The only difference is that there's no third terminal on this. The fan has its own capacitor so I'm assuming that isn't needed.
Another question I have is that the terminals aren't labeled. Should I follow the same terminal configuration or should I test the capacitor first? If so, I do have a multimeter, but wouldn't know how to test their polarity.
55 uf +6 - 6%, 440VAC, 50/60 Hz. The only difference is that there's no third terminal on this. The fan has its own capacitor so I'm assuming that isn't needed.
Another question I have is that the terminals aren't labeled. Should I follow the same terminal configuration or should I test the capacitor first? If so, I do have a multimeter, but wouldn't know how to test their polarity.
#6
04-21-20, 01:53 PM
Group Moderator
#7
04-22-20, 04:39 AM
Super Moderator
Some trivia about polarity marked capacitors for ac motors.
Some have + and - marked terminals.
What this normally means is that the terminal marked + is the lead that goes onto the center of the capacitor.
The - marked lead is connected to the electrolyte wrap near the outer casing which for run capacitors is usually a metal can.
There is no electrical difference when connecting these terminals but when you connect power to the + and the load to the - if the capacitor fails the hot terminal would be in the center of the wrap and less likely to energize the metal can.
Some have + and - marked terminals.
What this normally means is that the terminal marked + is the lead that goes onto the center of the capacitor.
The - marked lead is connected to the electrolyte wrap near the outer casing which for run capacitors is usually a metal can.
There is no electrical difference when connecting these terminals but when you connect power to the + and the load to the - if the capacitor fails the hot terminal would be in the center of the wrap and less likely to energize the metal can.
#8
04-22-20, 05:43 AM
orielonline, thanks for the old capacitor ratings. I concur with PJmax that new capacitor is electrically equivalent to original. PJmax, my post was not a question about the conclusion in your post. The ratings on the old capacitor were not readable on the photo on my screen so I asked for the info. What is wrong with that?
#9
04-22-20, 06:12 AM
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In looking at the pictures I'm wondering which side of the old cap was being used. I know the OP said "compressor" but we often hear "compressor" to mean the entire condensing unit. It's kind of unusual to see brown & yellow wires going to the compressor, yet quite common for them to go to the fan motor.
#10
04-22-20, 11:07 AM
Group Moderator
Usually the fan is purple and brown.
Yellow is start for the compressor.
In the case here..... the connections are on the HERM side of the capacitor.
Yellow is start for the compressor.
In the case here..... the connections are on the HERM side of the capacitor.
