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

Page: 85 / 174

4–51 T-365
AL65 DISCHARGE PRESSURE TRANSDUCER (DPT)
Cause: Compressor Discharge Transducer is out of range.
Component Compressor Discharge Transducer (DPT)
Troubleshooting Confirm accurate DPT pressure readings, refer to MANIFOLD
GAUGE SET
Section 7.2 .
Corrective Action Replace DPT if defective.
AL66 (SPT) SUCTION PRESSURE TRANSDUCER, (EPT) EVAPORATOR PRESSURE TRANSDUCER
Cause: Suction Pressure Transducer (SPT) out of range.
Component Suction Pressure Transducer (SPT)
Troubleshooting Confirm accurate EPT and SPT pressure readings, refer to MANI-
FOLD GAUGE SET
Section 7.2 . - Performing a Pre-trip 5-9 test will
also check the transducers.
Corrective Action Replace EPT/SPT if defective.
Troubleshooting Monitor
Corrective Action If the alarm persists, it may indicate a failing compressor, refer to
COMPRESSOR Service
Section 7.8 .
AL67 HUMIDITY SENSOR
Cause: Humidity Sensor (HS) reading out of range.
Component Humidity Sensor (HS)
Troubleshooting Make sure the humidity sensor is properly connected in the socket.
Corrective Action Make sure the humidity sensor wires have not been damaged.
Monitor, replace HS if alarm persists.
AL69 EVAPORATOR TEMP SENSOR (ETS1)
Cause: Evaporator Temperature Sensor (ETS1) out of range.
Component Evaporator Temperature Sensor (ETS1)
Troubleshooting Test the ETS1, refer to Sensor Checkout Procedure Section 7.25.1 .
Corrective Action Replace Evaporator Temperature Sensor (ETS1) if defective.
AL70 SECONDARY SUPPLY SENSOR (SRS)
Cause: Secondary Supply Sensor (SRS) is out of range.
Component Secondary Supply Sensor (SRS)
Troubleshooting Perform Pre-trip P5:
Corrective Action If P5 passes, no further action is required.
If P5 fails, replace the defective sensor as determined by P5, refer to
TEMPERATURE SENSOR Service
Section 7.25 .