Goodman GPG 16 M Series, Руководство по установке

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expansion valve, charge the system to sub-cooling, range
shown on chart, when necessary, adjust expansion valve
stem for superheat setting.
SUPERHEAT
Checking Superheat
Refrigerant gas is considered superheated whenever its
temperature is higher than the saturation temperature cor-
responding to its pressure. The degree of superheat equals
the degrees of temperature increase above the saturation
temperature at existing pressure.
1. Run system at least 10 minutes to allow pressure to
stabilize.
2. Temporarily install thermometer on suction (large) line
near compressor with adequate contact and insulate
for best possible reading.
3. Refer to the superheat table provided for proper sys-
tem superheat. Add charge to lower superheat or re-
cover charge to raise superheat.
Superheat Formula = Suct. Line Temp. - Sat. Suct. Temp.
Superheat Adjustment
NOTE:
The expansion valve will not need adjustment for
most applications. Ensure system superheat is set within
range listed on chart below.
Unscrew the cover from the expansion valve, locate the
adjustment screw, and turn it clockwise (in) to increase su -
perheat or counterclockwise (out) to decrease superheat.
Replace adjustment cap. Wait a minimum of 10 minutes be-
tween adjustments to allow time for the TXV and pressures
to stabilize.
Checking Subcooling
Refrigerant liquid is considered subcooled when its tem-
perature is lower than the saturation temperature corre-
sponding to its pressure. The degree of subcooling equals
the degrees of temperature decrease below the saturation
temperature at the existing pressure.
1. Attach an accurate thermometer or preferably a ther-
mocouple type temperature tester to the liquid line
close to the pressure switch.
2. Install a high side pressure gauge on the liquid access
fitting.
3. Record the gauge pressure and the temperature of the
line.
4. The difference between the thermometer reading and
pressure to temperature conversion is the amount of
subcooling.
Subcooling Formula = Sat. Liquid Temp. - Liquid Line
Temp.
EXAMPLE:
a. Liquid Line Pressure = 417
b. Corresponding Temp. °F. = 120°
c. Thermometer on Liquid line = 109°F.
To obtain the amount of subcooling, subtract 109°F from
120°F. The difference is 11° subcooling. See the specifica -
tion sheet or technical information manual for the design
subcooling range for your unit.
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 change -
over from cooling to heating is desired).
3. Set the room thermostat to the desired temperature.
TROUBLESHOOTING
Ignition Control Error Codes
The following presents probable causes of questionable unit
operation. Refer to Diagnostic Indicator Chart for an inter-
pretation of the signal and to this section for an explanation.
Remove the control box access panel and note the num-
ber 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-but-
ton 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.