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I only have four wires: Red, Blue, Yellow, and Green. My old thermostat jumps the R to RC and leaves C empty.
I have a new thermostat that wants 5 wires, but I don't have C. I am not sure what the circuit diagram is here, so I don't know if it's possible to make a new configuration that will give full functionality.
Here is my configuration:
Rc (jumper to red) R Red Y Blue C - W White G Green
What does add-a-wire do anyway? There is no extra wire so I would have to tear up my wall to run a new wire. I don't want to sacrifice independent fan control. What is the easiest way I can rewire this for a new thermostat?