Question: how to replace air conditioner thermostat?
Answer: Turn Off Power to A/C and Furnace. Better to be safe than sorry. ...  Remove Face of Old Thermostat. Take a Picture of the Wires. ...  Disconnect Wires from Old Thermostat. ...  Remove Old Mount. Put on the New Thermostat Mount and Connect Wires. ...  Screw Faceplate Mount to Wall. ...  Attach New Thermostat Face.