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9 69-2718EF—03
C
C
MCR33823
If you have an older thermostat with a
sealed mercury tube, turn to page 2
for proper disposal instructions.
Installing your thermostat
2 Remove old thermostat faceplate
and leave wires connected.
2a Take a picture of the wire
connections for later reference.
2b If no wire is connected to a terminal
labeled C or no C terminal exists
on the old thermostat, view the
Alternate Wiring videos at
wifithermostat.com/videos
Terminal
designation
Important! C wire is required and
is the primary power source for
your thermostat. Without a C wire,
your thermostat will not power up.