Replacing old thermostat
Note: Do not operate the cooling system when outside temperature is below 10
(50 ) to avoid
damaging the compressor.
Test the system to make sure that your heating and cooling systems are working properly before
installation. If either does not work, contact a heating/air conditioning service person to fix the
problem before installation.
TURN OFF POWER to system at the furnace, or at the fuse/circuit breaker panel.
Carefully unpack your new thermostat and mounting plate; save package of screws, instructions
and receipt.
Remove cover from old thermostat. If it does not snap off when pulled firmly from the bottom, check
for a screw used to secure the cover.
Loosen screws holding thermostat to the wall and lift away the thermostat.
Disconnect wires from old thermostat or sub-base. As you disconnect each wire, use masking tape
to label it with the old terminal designation. If there are only two wires, they don't need to be labeled.
If there is an extra wire that is not connected to your old thermostat, then you won't need to connect
it to the new thermostat.
Take care not to let the wires fall back into the wall or let the ends of the wires touch one another.
The wires are usually designated 'W', 'Y', 'G', 'RH', 'RC', 'H1', 'H2'.
°C
°F
26