REMOVE OLD THERMOSTAT
1. Shut off electricity at the main fuse box until installation is
complete. Ensure that electrical power is disconnected.
2. Remove the front cover of the old thermostat. With wires
still attached, remove wall plate from the wall. If the old
and the wall mounting plate as an assembly.
3. Identify each wire attached to the old thermostat using
the labels enclosed with the new thermostat.
4. Disconnect the wires from old thermostat one at a time.
DO NOT LET WIRES FALL BACK INTO THE WALL.
5. Install new thermostat using the following procedures.
(below Fan switch)
This product does not contain mercury. However, this product
may replace a unit which contains mercury.
Do not open mercury cells. If a cell becomes damaged, do not
touch any spilled mercury. Wearing nonabsorbent gloves, take
up the spilled mercury and place into a container which can be
Figure 1. Thermostat Base
Mercury must not be discarded in household trash. When the
unit this product is replacing is to be discarded, place in a
suitable container and return to White-Rodgers at 9797 Reavis
Road, St. Louis, MO, 63123-5398 for proper disposal.
O/B TERMINAL SWITCH SELECTION
The O/B switch on this thermostat is factory set to the “O”
position. This will accommodate the majority of heat pump
applications, which require the changeover relay to be ener-
gized in COOL. If the thermostat you are replacing or the heat
pump being installed with this thermostat requires a “B” termi-
nal, to energize the changeover relay in HEAT, the O/B switch
must be moved to the “B” position.
ATTACH THERMOSTAT BASE TO WALL
1. Remove the packing material from the thermostat. Gently pull
the cover straight off the base. Forcing or prying on the
thermostat will cause damage to the unit.
2. Connect wires beneath terminal screws on base using
appropriate wiring schematic (see figs. 2 through 4).
CHECK THERMOSTAT OPERATION
If at any time during testing your system does not operate
properly, contact a qualified service person.
3. Place base over hole in wall and mark mounting hole
locations on wall using base as a template.
Turn on power to the system.
4. Move base out of the way. Drill mounting holes.
5. Fasten base loosely to wall, as shown in fig. 1, using two
mounting screws. Place a level against bottom of base,
adjust until level, and then tighten screws. (Leveling is for If your system does not have a G terminal connection, skip to
appearance only and will not affect thermostat operation.) If Heating System.
you are using existing mounting holes, or if holes drilled are
too large and do not allow you to tighten base snugly, use
plastic screw anchors to secure subbase.
1. Move fan switch to ON position. The blower should begin to
2. Move fan switch to AUTO position. The blower should stop
6. Push excess wire into wall and plug hole with a fire-resistant
affecting thermostat operation.
1. Move SYSTEM switch to HEAT position. If the auxiliary
ELECTRIC/GAS JUMPER (Fan Option)
heating system has a standing pilot, be sure to light it.
Read the following information before clipping the nonelectric
heat jumper. If you are unsure of your application, contact a
qualified service person.
to adjust thermostat setting to 1° above room
temperature. The Heat Pump system should begin to oper-
ate. However, if the Flame icon ( ) and Snowflake icon ( )
are flashing, the compressor lockout feature is operating.
jumper, W904, on the thermostat base must be cut (see fig. 1).
3. Adjust temperature setting to 4° above room temperature.
The auxiliary heat system should begin to operate and tehe
Flame icon will be flashing.
If your emergency or auxiliary heat system requires that the
thermostat energize the fan circuit, do not cut jumper W904.
to adjust temperature setting below room tem-
perature. The heating system should stop operating.
With two "AA" batteries installed, your thermostat will continu-
ously display the temperature during a loss of AC power.