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To which (two ) terminals on the furnace PC board

To which (two ) terminals on the furnace PC board do I attach the low voltage wires from the contactor in the A/C condensing unit?

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Hi, at the PC board, you will connect the red to the R terminal, and yellow if that's the color they used to the Y terminal which may have a wire from the stat on it already. This will close the contacts on the contactor on a call from the thermostat for cooling. Please be kind when rating me as I know you will. Thank you.
A/C, Heating, & Refrigeration Contractor
PS, if you run the wires and connect to R and C for common, the outdoor condenser will run all of the time on its own. It will have 24 volts straight to it constantly.

Posted on Jul 30, 2010


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