White Rodgers 7904 Thermometer User Manual


 
2
INSTALLATION
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
thermostat has a wall mounting plate, remove the thermostat
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.
ELECTRIC HEAT OR SINGLE-STAGE
HEAT PUMP SYSTEMS
Read entire paragraph before setting electric heat switch. If you
are unsure of your application, contact a qualified serviceperson.
If you have a single-stage heat pump system, OR your system
uses central electric heat, then you must move the switch on the
back of the thermostat base to the electric heat position (see fig
1). The electric heat position is to the left. Use a small screw-
driver or pencil to move the switch.
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. If necessary, move
the electric heat switch (see ELECTRIC HEAT SYSTEMS,
above).
2. Connect wires beneath terminal screws on base using
appropriate wiring schematic (see figs. 3 through 10).
3. Place base over hole in wall and mark mounting hole
locations on wall using base as a template.
4. Move base out of the way. Drill mounting holes.
5. Fasten base loosely to wall, as shown in fig. 2, using two
mounting screws. Place a level against bottom of base,
adjust until level, and then tighten screws. (Leveling is for
appearance only and will not affect thermostat operation.) If
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.
6. Push excess wire into wall and plug hole with a fire-resistant
material (such as fiberglass insulation) to prevent drafts from
affecting thermostat operation.
BATTERY LOCATION
This thermostat requires 3 “AA” alkaline batteries to oper-
ate. Batteries are included. Install the batteries along the top
of the base (see fig. 2). The batteries must be installed with the
positive (+) ends to the left.
If the word BATTERY is displayed, the batteries are low and
should be replaced with fresh “AA” Energizer
®
alkaline batteries.
HYDRONIC (HOT WATER OR STEAM)
HEATING SYSTEMS
This thermostat is set to operate properly if you have a forced-
air heating system. If you have a hydronic heating system (a
system that heats with hot water or steam), you must set the
thermostat to operate properly with your system. To change the
setting, press and hold SET TIME and VIEW PRGM buttons at
the same time until the correct setting is displayed (A for forced
air; H for hydronic systems).
If you do not press both buttons at the same time, A or H will not
be displayed. If this happens, press RUN PRGM, then press and
hold SET TIME and VIEW PRGM at the same time.
NOTE
ELECTRIC GAS
Figure 1. Back of thermostat base
Electric/Gas switch
Figure 2. Thermostat base
Mounting
holes
Screw anchors
Alkaline batteries (3 “AA”–
install “+” ends to the left)
W
RH
B
Y
O
G
RC