Carrier 69NT40-561-300, Operation And Service Manual

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4–47 T-365
AL28 LOW SUCTION PRESSURE
Cause: Suction pressure too low for normal operation
Component N/A
Troubleshooting Power cycle the unit.
Corrective Action Resetting the unit may correct problem, monitor the unit.
Component Suction Pressure Transducer (SPT)
Troubleshooting Confirm accurate SPT pressure readings, refer to MANIFOLD
GAUGE SET
Section 7.2
Corrective Action Replace SPT if defective
Component Discharge Pressure Transducer (DPT)
Troubleshooting Confirm accurate DPT pressure readings, refer to MANIFOLD
GAUGE SET
Section 7.2
Corrective Action Replace DPT if defective
AL29 AUTOFRESH FAILURE
Cause: Alarm 29 is triggered if CO
2
or O
2
level is outside of the limit range and the vent position is at 100%
for longer than 90 minutes.
Component Alarm LED will be activated and user intervention is required.
Troubleshooting Refer to eAutoFresh manual.
Corrective Action The alarm is triggered off when atmospheric conditions are within lim-
it settings.
AL50 AIR VENT POSITION SENSOR (VPS)
Cause: VPS Sensor out of range.
Component Vent Position Sensor (VPS)
Troubleshooting Make sure VPS is secure.
Corrective Action Manually tighten panel.
Troubleshooting If the alarm persists, replace the sensor or the assembly.
Corrective Action Replace VPS.