Honeywell CHRONOTHERM III T8611G - Manual (Page 6)

Fig. 9—Mounting the thermostat on subbase.
When the batteries are low, the display will flash REPL
BAT. Homeowner will have 20-30 seconds to replace batter-
ies after removing batteries from thermostat. After 20-30
seconds, it will be necessary to reprogram. REPL BAT
indication will be disappear when thermostat is mounted
back on the powered subbase.
MOUNTING THE THERMOSTAT
With system switch set to OFF, hang the thermostat on the
tabs at the top of the subbase (Fig. 9A). Swing down and press
on lower edge until thermostat snaps in place
(Fig. 9B). Open cover and tighten the captive mounting
screws (Fig. 9C).
SETTING DAY AND TIME
Restore 24V power to the thermostat. When power is
applied to the thermostat, the display will read 1:00 PM and
room temperature. It will go off for a few seconds, then begin
to flash on and off. Set present day and time.
6
AHEAD
BACK
SET
PRESENT
DAY/TIME
DAY
Press .
Press to set the current day. Each press of the
DAY key advances the display one day.
Press TIME or to set the current time.
If the display will not come on.
—check mounting of thermostat to subbase. If loose or
misaligned, remove thermostat and reinstall on the
subbase, making sure it is firmly attached.
—check to see that system power is on.
—check voltage between R and C/X; it should be 20 to 30
Vac.
Checkout
CAUTION
During cold weather, some heat pumps will require
that crankcase heater be energized several hours
before operating heat pump. Refer to manufacturer’s
recommendations.
HEATING
When heating setting is changed, thermostat will wait up
to 5 minutes before turning on the heating equipment. This
delay protects the compressor.
Move the system switch to HEAT and the fan switch to
AUTO. Press WARMER key until the setting is about
10
° F [6° C] above room temperature. Heating should start
and the fan should run (there may be a delay of
5-10 minutes before heat turns on). Press COOLER key until
the setting is about 10
° F [6° C] below room temperature. The
heating equipment and fan should shut off.
NOTE: On an AUTO changeover thermostat, the cooling
temperature must be set at least 3 ° F [1.7° C] above the
heating temperature, or display will flash.
COOLING
CAUTION
Do not operate cooling if outdoor temperature is
below 50
° F [10° C]. Refer to manufacturer’s
recommendations.
!
!
NOTE: When cooling setting is changed, thermostat will
wait up to 5 minutes before turning on the cooling equip-
ment. This delay protects the compressor.
Move the system switch to COOL and the fan switch to
AUTO. Press COOLER key until the setting is about
10
° F [6° C] below room temperature. The cooling equip-
ment and fan should start. Press WARMER key until the
setting is about 10
° F [6° C] above room temperature. The
cooling equipment and fan should stop.
NOTE: On an AUTO changeover thermostat, the heating
temperature must be set at least 3 ° F [1.7° C] below the
cooling temperature, or display will flash.
FAN
Move the system switch to OFF, and the fan switch to ON.
The fan should run continuously. When the fan switch is in
the AUTO position, fan cycles with the heating or cooling
system.
INSTALLER SELF-TEST (OPTIONAL)
NOTE: Thermostat must have AC power to perform self-
test.