Troubleshooting - Amana A/GPDM3 Series Installation Instructions Manual

Refrigerant Charge Check
NOTE: For optimal performance, follow charging instruc-
tions below.
(Units with Fixed Orifice Devices)
All package units with fixed orifice devices are charged
using the superheat method at the compressor suction line.
To increase super heat, remove charge and to decrease
super heat, add charge. After superheat is adjusted, it is
recommended to check unit subcooling at the condenser
coil liquid line. See Design Superheat and Subcooling table
for targets on each model.
(Units with Expansion valve (TXV))
Single Stage Cooling Application: Refer to the Design Su-
perheat & Subcooling table
Two-Stage Cooling Application: Run unit on Low Stage
cooling and refer to Design Superheat & Subcooling table.
1. Purge gauge lines. Connect service guage manifold
to access fittings. Run system at least 10 minuets to
allow pressure to stabilize.
2. Temporarily install thermometer on liquid (small) line
near liquid line access fitting with adequate contact
and insulate for best possible reading.
3. Check subcooling and superheat. System should have
a subcooling and superheat within the range listed on
the Design Superheat and Subcooling table.
a. If subcooling and superheat are low, adjust TXV
superheat, then check subcooling.
NOTE: To adjust superheat, turn the valve stem
clockwise to increase and counterclockwise to
decrease.
b. If subcooling is low and superheat is high, add
charge to raise subcooling then check superheat.
c. If subcooling and superheat are high, adjust TXV
valve superheat, then check subcooling.
d. If subcooling is high and superheat is low, adjust
TXV valve superheat and remove charge to lower
the subcooling.
NOTE: Do NOT adjust the charge based on suction
pressure unless there is a gross undercharge.
4. Disconnect manifold set, installation is complete.
Design Superheat & Subcool
Superheat
Model
±2°F
A/GPDM324**41 17
A/GPDM330**41 10
A/GPDM336**41 8
A/GPDM342**41 8
A/GPDM348**41 13
Outdoor
Expansion Cooling
Ambient
Device Stage
Piston High
Piston High
Piston High
Piston High
Piston High
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.
Ignition Control Error Codes
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
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.
Abnormal Operation - Heating
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, 30 second inter-
purge cycle is completed, and ignition is re-attempted. The
(°F )
control will repeat this routine three times if a measurable
95
combustion is not established. The control will then shut off
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the induced draft blower and go into a lockout state.
95
95
If flame is established but lost, the control will energize
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the circulator blower at the heat speed and then begin a
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TROUBLESHOOTING