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On outside compressor for whole house AC: Critters ate wires. Have Blk & Red power in from breaker. 24vac switched from thermostat. 1 contactor with 24vac coil(original). 1 Capacitor w/ 3 terms labeled: C, fan, herm. compressor w/ 3 wires: #10 yel & blk, #14 red. fan w/ 3 # 18 wires: Blk, Orn, Blu. I need wiring. Here is what I think: All blacks connect together. Red power wire connects to contactor in. Fan orn & Compressor Yel go to contactor out. Capacitor is the problem. "C" marked terminal goes to contactor out. "fan" marked term goes to fan blue. "Herm" marked term goes to compressor Red. Is this correct? and what ther heck doas "HERM" saand for?

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  • Dennis Boxerman May 11, 2010

    "Herm" means a hermatic compressor. Type that is what is commonly called a "Can" compressor. It is a non-rebuildable type. Your capacitor is a dual type. "C" is common. It supplies power to both sides of the capacitor. One source of power in and 2 sources out. Can you get make, model, and serial? If so, maybe I can come up with what you need.



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There should be a wiring diagram on the back of the access panel. If you can't read it, check online for model wiring diagram. Don't guess, you may cause more expensive damage.

Posted on Jun 26, 2009


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