The power should be turned off for the A/C and furnace. It is better to be safe than sorry. Is that correct? The face of the old thermostat should be removed. Take a picture of the wire. Is that correct? There are wires to the old Thermostat. Is that correct? The Old Mount needs to be removed. Attach the Thermostat Mount to the wire. There is a screw faceplate mount to the wall. Is that correct? Attach a new Thermostat face.
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