I bought a new WiFi thermostat and it requires 5 wires and I only have 4 currently.

I will run a new set of wires from the thermostat to board, however on the board it shows that I have a C wire but that wire does not go to thermostat, I believe it goes to unit outside as that wire is attached to another set of 2 thin cables and it does not to go thermostat.

My question is: when I run the new set of wires, can I just attach the C cable into that splice?

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    Jul 24, 2020 at 14:23


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