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6
B.
110/120V
H
C
H
C
A.
A150045
!
Warning!
If your old thermostat is labeled 110V or
120V, or is connected by thick wires and wire nuts,
it is a high voltage system and is not compatible
STEP 2. POWER OFF YOUR HEATING AND COOLING SYSTEM
1.
Turn off the power to your heating and cooling system.
a. You can do this either at your circuit breaker box or a switch at
your indoor furnace or fan coil.
b. Most systems have one switch, but some systems or systems
with Rh and Rc and C wires noted in Step 1 will have two switch-
es.
2.
Make sure your system is without power by using your old thermostat
to adjust the temperature. Your system should not turn on.