Honeywell RTH7400 Série Guide D'installation Rapide page 2

Quick Installation Guide
Read and save these instructions
Removing your old thermostat
1
Turn power OFF.
To protect yourself and your
equipment, Turn off the power at the
breaker box or switch that controls
your heating/cooling system.
2
Check that your system is off.
Change the temperature on your
old thermostat. If you don't hear the
system turn on within 5 minutes, the
power is off.
Note: If you have a digital
thermostat that has a blank display,
skip this step
3
Remove the old thermostat's
faceplate.
On most thermostats, you can take
off the faceplate by grasping and
gently pulling. Some thermostats
may have screws, buttons, or clasps.
Do not remove any wires from your
thermostat at this time!
4
Make sure there are no
120 V/240 V wires.
Do you have thick black wires with
wire nuts?
Is your thermostat 120 V or higher?
If you answered yes to either of
these questions, you have a line
voltage system and the thermostat
will not work.
If you are unsure visit:
resideo.com
Breaker box
ON
OFF
75
Wire nut
Thick black wire
2
ON
OFF
OFF
Switch
75