Carrier NDK33BN0KB, Operation & Service Manual

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62-61753-21 7-19
Alarm
NO.
Steps ALARM / CAUSE CORRECTIVE ACTION
24 COMPRESSION RATIO EXCEEDED

TRIGGER ON: If the compressor compression ratio is greater than 21 for 20 seconds.

UNIT CONTROL: Engine operation: Engine and unit shutdown and alarm.
Standby operation: Refrigeration system shutdown and alarm with PSCON
still energized.

RESET CONDITION: Auto reset when compression ratio is less than 21 for 3 minutes or,
alarm may be manually reset via keypad or by turning the unit off, then back on again.
NOTE: Follow the steps below until a problem is found. Once a repair or correction has been made, the active
alarm should clear itself (refer to reset condition above). Operate the unit through the appropriate modes to see if
any active alarm occurs. Continue with the steps below as necessary.
1 Look for high discharge or low suc-
tion pressure causes. Discharge and suction pressures must be in normal
range for the current ambient and refrigerated com-
partment temperature conditions. Refer to Abnormal
Pressure Trouble Shooting Section 9.4.7.