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C
S
OOLING
TARTUP
NOTE: Check all manual reset limit controls in heating circuit if cool-
ing mode does not operate.
Compressor Protection Devices
The compressor includes components which are designed to
protect the compressor against abnormal operating conditions.
T
O PREVENT PERSONAL INJURY OR DEATH, ALWAYS DISCONNECT ELECTRICAL
POWER BEFORE INSPECTING OR SERVICING THE UNIT.
PROTECTION DEVICES RESET AUTOMATICALLY, ENERGIZING THE CONTACTOR
AND OUTDOOR FAN.
Refrigerant Charge Check
After completing airflow measurements and adjustments the
unit's refrigerant charge must be checked. The unit comes
factory charged, but this charge is based on 325 CFM per ton
and minimum ESP per AHRI test conditions (generally
between .15 -.28 ESP). When air quantity or ESP is different
than above, the refrigerant charge must be adjusted to the
proper amount. All package units with fixed orifice devices
are charged using the super heat method at the compressor
suction line.
After superheat is adjusted it is recommended to check unit
sub-cooling at the condenser coil liquid line out. For charge
adjustments, see superheat and sub-cooling charts shown
for each model.
Cooling Refrigerant Charging (Models with TXV)
Check unit charge before putting the cooling section into full
operation. The unit has a thermostatic expansion valve
metering device. To ensure the unit is properly charged for
the intended application, check the unit refrigerant sub-
cooling at the condenser. The refrigerant sub-cooling is a
function of outdoor ambient temperature and return air
temperature of the conditioned space. It is the installing
contractors responsibility to ensure the proper refrigerant
sub-cooling at the condenser is adjusted for each application.
As the outdoor ambient temperature rises the sub-cooling
decreases and as the outdoor ambient temperature lowers,
the sub-cooling increases. NOTE: Proper sub-cooling
adjustment optimizes cooling performance. Models equipped
with thermostatic expansion valve, charge the system to sub-
cooling, range shown on chart, when necessary, adjust
expansion valve stem for superheat setting.
Superheat Adjustment
To adjust superheat, remove the control box cover and locate
the expansion valve on the liquid line of the evaporator.
Unscrew the cover from the expansion valve, locate the
adjustment screw, and turn it clockwise (in) to increase
superheat or counterclockwise (out) to decrease superheat.
Replace adjustment cap. Wait a minimum of 10 minutes
between adjustments to allow time for the TXV and pressures
to stabilize.
NOTE: The expansion valve will not need adjustment for most
applications. Ensure system superheat is set within range listed
on chart.
WARNING
A
LL COMPRESSOR
Design superheat & subcooling @ 95 °F
outdoor ambient temperature
Models #
*PG1424***M
*PG1430***M
*PG1436***M
*PG1442***M
*PG1448***M
*PG1461***M
Cooling Operation
NOTE: Mechanical cooling cannot be reliably provided at ambient
temperatures below 50° F.
1. Turn on the electrical power supply to the unit.
2. Place the room thermostat selector switch in the COOL
position (or AUTO if available, and if automatic changeover
from cooling to heating is desired).
3. Set the room thermostat to the desired temperature.
TROUBLESHOOTING
I
C
E
GNITION
ONTROL
RROR
The following presents probable causes of questionable unit
operation. Refer to Diagnostic Indicator Chart for an
interpretation of the signal and to this section for an explanation.
Remove the control box access panel and note the number of
diagnostic LED flashes. Refer to Diagnostic Indicator Chart
for an interpretation of the signal and to this section for an
explanation.
Fault Recall (Two-Stage Models ONLY)
The ignition control is equipped with a momentary push-button
switch that can be used to display on the diagnostic LED the
last five faults detected by the control. The control must be in
Standby Mode (no thermostat inputs) to use the feature.
Depress the push-button switch for approximately 2 seconds.
NOTE: Do not hold for longer than 4 seconds. Holding the
button for 4 seconds or higher will erase the memory!
Release the switch when the LED is turned off. The diagnostic
LED will then display the flash codes associated with the last
five detected faults. The order of display is the most recent
fault to the least recent fault.
A
O
BNORMAL
PERATION
Internal Control Failure
If the integrated ignition control in this unit encounters an
internal fault, it will go into a "hard" lockout and turn off the
diagnostic LED. If diagnostic LED indicates an internal fault,
check power supply to unit for proper voltage, check all fuses,
circuit breakers and wiring. Disconnect electric power for five
seconds. If LED remains off after restoring power, replace
control.
External Lockout
An external lockout occurs if the integrated ignition control
determines that a measurable combustion cannot be
established within three (3) consecutive ignition attempts. If
flame is not established within the seven (7) second trial for
ignition, the gas valve is de-energized, 15 second inter-purge
17
Superheat ± 2°F Subcooling ± 3°F
12
11
5
15
6
11
10
12
4
12
11
11
C
ODES
- H
EATING
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