Specifications

7
5. Economizer — 1st stage cooling
6. Automatic Changeover from Heat to Cool
The battery maintains the stored program in the event of
a power failure. When attached to the wall with 24vAC
power applied, the thermostat will function normally with-
out the battery. However, the program will be lost in the
event of power interruption or failure if the battery is not
installed. When power is restored, the thermostat will
automatically maintain a temperature of 64°F or a cooling
temperature of 82°F (factory preprogrammed) as needed.
CHECK THERMOSTAT OPERATION
When checking thermostat, option switch #4 for auto-
matic changeover must be in the OFF position. This will
allow temporary setting of heat set points above cool
settings. After system checkout, reset option switch to ON
position if automatic changeover is desired (see SET
OPTION SWITCHES).
FAN OPERATION
1. Turn on power to the system. If the auxiliary heat
source has a standing pilot, be sure to light it.
2. Press
FAN
ON – AUTO
until FAN is displayed. The blower
should begin to operate.
3. Press
FAN
ON – AUTO
until FAN is displayed. The blower
should stop operating within approximately one
minute.
HEATING SYSTEM
1. Press
SYSTEM
HEAT-OFF-COOL-AUTO
until HEAT is displayed. (It should
already be displayed.)
2. Press to adjust thermostat to 99°F. All stages
of the heating system should come on within approxi-
mately five minutes. However, if the PUMP LED is
flashing, the compressor lockout feature is operating
(see Lockout Bypass Option to temporarily over-
ride the compressor lockout feature during testing).
LOCKOUT BYPASS OPTION
FOR QUALIFIED SERVICE TECHNICIANS’ USE
ONLY. OPERATORS SHOULD NOT USE THIS
FEATURE DUE TO POSSIBILITY OF EQUIP-
MENT OR PROPERTY DAMAGE, OR PER-
SONAL INJURY.
DO NOT USE THE LOCKOUT BYPASS OP-
TION UNLESS THE COMPRESSOR OIL HEAT-
ERS HAVE BEEN OPERATIONAL FOR 6
HOURS AND THE SYSTEM HAS NOT BEEN
OPERATIONAL FOR AT LEAST 5 MINUTES.
COMPRESSOR LONG TERM CYCLE
PROTECTION
To protect the compressor from potential damage due
to temperature change of crankcase oil, this thermo-
stat has a built-in time delay of one hour less than the
power loss to the unit (up to 12 hours maximum
lockout). During this time, auxiliary heat will be used
when necessary to maintain setpoint temperature.
DO NOT attempt to override this delay feature before
crankcase temperature has stabilized (for example, if
power has been out for three hours, the compressor
should remain locked out for two hours).
COMPRESSOR SHORT TERM CYCLE
PROTECTION
This thermostat has a built-in short term (5-minute)
time delay. During this 5-minute period, the thermo-
stat will lock out the compressor to allow head pres-
sure to stabilize. If you want to override this feature
while testing thermostat operation, simply press
ADV
PRGM
and
HOLD
TEMP
buttons at the same time at initial
startup.
NOTE
NOTE
CAUTION
!
CAUTION
!
ON
1234
Switch #1 (see steps 1-4)
Switch #2 (see steps 1-4)
Switch #3
Switch #4
(
see step 6
)
ON
W1 Y2
When using economizer with
single stage heat pump, field
jumper W1 & Y2
ON
1234
Switch #1 (see steps 1-4)
Switch #2 (see steps 1-4)
Switch #3 (see step 5)
Switch #4 ON
3. Press
SYSTEM
HEAT-OFF-COOL-AUTO
so that EMER is displayed. Repeat
step 2.
4. To program the thermostat, see OPERATION GUIDE.
COOLING SYSTEM
To prevent compressor and/or property damage,
if power to the compressor has been off or
interrupted for more than 1 hour and the outdoor
temperature is below 50°F, DO NOT operate the
system for at least the amount of time the com-
pressor was off! This will allow the compressor
heaters to warm the compressor oils to avoid
damage due to slugging.