Turn off the power to the Heating/Air
Conditioning system at the main fuse
panel. Most residential systems have
a separate breaker for disconnecting
power to the furnace.
Remove the cover of the old thermostat.
If it does not come off easily check for
screws.
Loosen the screws holding the thermostat
base or subbase to the wall, and lift away.
Disconnect the wires from the old
thermostat. Tape the ends of the wires
as you disconnect them, and mark them
with the letter of the terminal for easy
reconnection to the new thermostat.
STEP #2
REMOVE OLD THERMOSTAT
Page 20
Keep the old thermostat for reference
purposes, until your new thermostat is
functioning properly.