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I'm using a blue wire as a c-wire, however when I went to connect the blue wire at the furnace, it already had a white wire ( not from a thermostat) corrected to the c-terminal. Can / wires be connected to c terminal? If not, what do I do with the white wire?


marked as duplicate by Doresoom, Ecnerwal, DMoore, Tester101 May 18 '15 at 11:58

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You can connect multiple wires to the same C terminal. The other one is likely going to the outside AC unit.

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