2
Tools you will need
You may need
Wire stripper
Needle-nose pliers
Drill and
drill bit (7/32 in)
Smartphone
To install your
thermostat and
photograph existing
wiring.
Honeywell Home app
To configure your
system and connect to
your smartphone.
Small flat head screwdriver
Phillips screwdriver
Pencil
Level
Home Wi-Fi
Password
Compatibility
• Compatible with most heating, cooling, and heat pump systems
• Required: 24 VAC power (“C” wire). C-Wire Power Adapter Included to
provide power if needed
• Does not work with electric baseboard heat (120-240V)
• Does not work with millivolt systems
• Does not support input (S terminals) for indoor and outdoor sensors
• Does not support relay (U terminals) for ventilation
• Android or iOS smartphone, tablet, or device
For help, contact
WEB
honeywellhome.com/support
PHONE
1-800-633-3991
SOCIAL
Twitter: @Honeywell_Home, Facebook: Honeywell Home
CAUTION: MERCURY NOTICE
If this product is replacing a control that contains mercury in a sealed tube, do not
place the old control in the trash. Contact your local waste management authority for
instructions regarding recycling and proper disposal.
CAUTION: EQUIPMENT DAMAGE HAZARD
Compressor protection is bypassed during testing. To prevent equipment damage,
avoid cycling the compressor quickly.
CAUTION: ELECTRICAL HAZARD
Can cause electrical shock or equipment damage. Disconnect power before beginning
installation.
REQUIRED: 24 VAC POWER (“C” WIRE)
C-Wire Power Adapter Included to provide power if needed.
Removing your old thermostat
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 thermo-
stat that has a blank display, skip
this step.
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.
3
Remove your old thermostat from
the wall plate
On most thermostats, you can take
off the thermostat by grasping and
gently pulling. Some thermostats
may have screws, buttons, or
clasps.
Do not remove any wires from
your thermostat at this time!
75
OFF
OFF
ON
OFF
OFF
ON
75
Breaker box
Switch
5
Take a picture of how your wiring
looks right now
Be sure to include the letters
next to the terminals where the
wires are inserted. This will be a
helpful reference when wiring your
thermostat.
Tip:
If the color of your wires has
faded or if 2 terminals have the
same wire color, use the wire
labels provided in the package to
label each wire.
4
Make sure there are no
120/240V wires
Do you have thick black wires
with wire nuts?
Is your thermostat 120V 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:
honeywellhome.com/support
6
Remove any jumpers
A jumper connects one terminal to
another terminal. It may look like
a small staple or even a colored
wire and must be removed before
continuing.
Use a screwdriver to
release wires from terminals.
The thermostat does not
need jumpers.
Y R RC
Example of
a jumper
Wire nut
Thick black wire
Terminals
1/4” to 3/8”
Read and save these instructions.
