Carrier PrimeLINE 69NT40-561-200, Operation And Service Manual

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4–31 T-362
AL08 High Compressor Pressure Ratio
Cause:
Controller detects discharge pressure to suction pressure ratio is too high.
The controller will attempt to correct the situation by restarting the compressor.
Component
Discharge Pressure Transducer (DPT)
Troubleshooting Confirm accurate DPT pressure readings. See Manifold Gauge Set Section 7.2 .
Corrective Action
Replace DPT if defective.
AL09 O2 Sensor Failure
Cause: Triggered anytime the O
2
sensor reading is outside of the normal operation range, after an initial signal
was detected.
Component
O
2
Sensor, O
2
Amplifier, Sensor Switch Module (if equipped)
Troubleshooting Check Cd44 and scroll down to 02V. The O
2
sensor output will be displayed in
millivolts (130mV to 4100mV).
Switch equipped: If voltage is not present at Cd44 and a sensor switch module is
installed, check for O
2
voltage on the black wire connected to the sensor switch
module, connecting ground of meter to TP9. If the voltage is in the 130mV to 4.1V
range, directly wire the black wire to KD04. This may cause an AL07 depending
on O
2
reading but XtendFRESH will operate normally. If no voltage on the black
wire, proceed to next step.
Check wiring (see schematic), and correct if found mis-wired.
If O
2
sensor is available, remove the upper fresh air panel and evaporator motor
and replace the sensor. If after replacing sensor AL09 continues, replace
amplifier.
If parts are not available, turn XtendFRESH option off at code Cd43 and open the
Manual Fresh Air Vent.
AL10 CO2 Sensor Failure
Cause:
Triggered anytime the CO
2
sensor reading is outside of the normal operation range, after an initial signal
was detected.
Component CO
2
Sensor
Troubleshooting
Check the voltage at MC5 to the ground pin on TP9 (1 - 4.7 vdc).
Check wiring (see schematic), and correct if found mis-wired.
If part is available, remove upper fresh air panel and evaporator motor; replace
sensor. If no part is available, take no action and service at next PTI.
XtendFRESH will continuously run the scrubber. O2 level will be controlled with
the opening and closing of the fresh air vents as required.
Corrective Action The alarm is triggered off when voltage is within operating range.
AL14 Phase Sequence Detect Fault
Cause:
Controller is unable to determine the correct phase relationship.
Component N/A
Troubleshooting
Power cycle the unit.
Corrective Action Resetting the unit may correct problem, monitor the unit.
Component
Wiring
Table 4–5 Alarm Indications and Descriptions