How do I replace a 3-wire thermostat with a 4-wire thermostat?
We bought a Honeywell thermostat with four wires and our current Mears model has 3 wires colored black, red, and white. The wires on the Honeywell model are 2 red and 2 black. How, if possible, can we use this thermostat with the current wiring?
I am not sure Honeywell thermostats work for every situation...I just replaced my 3 wire thermostat with a digital, and it had all kinds of universal hook-ups for different configurations. I am attaching a long discussion on this topic. I hope you find
Two wires connect the control device (which could be a thermostat, float switch, limit switch or other contact device) to the magnetic