Cooling System - Carrier TP-WEM01 Installation Manual

STEP 2. POWER OFF YOUR HEATING AND
COOLING SYSTEM
Turn off the power to your heating and cooling system. You can
do this either at your circuit breaker box or a switch at your
indoor furnace or fan coil. Most systems have one switch, but
systems with Rh, Rc, and C wires noted in Step 1 will have two
switches.
Make sure your system is without power by using your old
thermostat to adjust the temperature. Your system should not
turn on.
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