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I am looking to install a new thermostat that will require a C wire. I have a single stage A/C unit and my current thermostat has Rc, G, and Y wires. There is also an unused blue wire which I traced to the A/C unit electrical panel - it is not connected to anything. My problem is - the guys that installed my A/C were kind of "half ass" and there is no easy way for me to just connect the unused blue wire in the A/C electrical panel. The unused blue wire is wrapped around the brown wire.