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Thermostat Wiring to a Furnace and AC Unit! Color Code, How it Works, Diagram!

In this HVAC Installation Training Video, I show How to Wire the Low Voltage Thermostat Wires into a Furnace and AC Unit. I Explain what each of the Letter Terminals are for, the Voltage Path, How it Works, and also the Normal Color Code Used. I discuss how to Wire the Contactor and what the difference is between the Rc and the R Terminals.

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