How to Replace an Old Style Home Thermostat
- 1). Turn the power off to the furnace. A switch should be located on the side of the furnace to turn power to it off. If not, turn off the correct circuit breaker in the circuit breaker panel.
- 2). Remove the old style home thermostat from its wall plate by gently pulling it off. Unscrew the thermostat wires, and label them to which lettered terminal they were connected to. You will use that information later to reconnect them to the new thermostat.
- 3). Remove the wall plate by unscrewing it. Mount the new wall plate with drywall anchors and screws. Check it with a level before securing the screw tight, and adjust as necessary.
- 4). Reconnect the thermostat wires to the thermostat. Refer to the labels to make sure you connect them to the correct terminals.
- 5). Push the thermostat onto the wall plate until it snaps into place. Plastic tabs should be on the wall plate that will hook into the thermostat.
- 6). Turn the power to the furnace back on. Adjust your thermostat to your preferred setting. If you did replace it with a programmable thermostat, read the instruction manual before programming it.
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