AC capacitor test

 if the capacitor marked 45/5 for example, then the Fan to common should be tested around 5 mfd, then the Herm to common should be tested around 45 mfd, there should be also +- like 6%, that will give a range. If they are out of the range, then the capacitor should be replaced. Also if capacitor is bad, when you manually push the contact, the condenser will try to start with some sound, but eventually it cannot, with this test, you can pretty much confirm that the system most likely need have capacitor replaced.

in terms of the wiring, herm goes to condenser, fan goes to fan, common goes to L2.

in terms of the color code, fan wire should be brown, common should be blue, herm should be yellow, but sometimes the color get messed up, you will have to make sure the wire (whatever the color might be) are connected to the right terminal.

So to make it even more clear is that the herm terminal on capacitor should be connected to the compressor S(tart) terminal. C(ommon) on capacitor should be connected to L2 and C(common) on compressor should be connected to L1, just make sure that capacitor C and compressor C are connected to different Line (normally black and red wires off of contact). Please see the graph below.




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