C3 Check Defrost Termination 1Temperature Sensor

Compartment 3 defrost termination temperature sensor is out of range, and the unit alarms and initiates defrost based on the return air sensor condition.

Defrost Termination Temperature Sensor for Compartment 3, (3DTT) is not within the range of -53° to +158°F (-47° to +70° C.)

Engine and Electric Operation: If Alarm 138 C3 CHECK RETURN AIR SENSOR is not active: alarm and initiate defrost if 1RAT is below 455F (7.25C). If Alarm 138 is also active: alarm and initiate defrost if 1SAT is below 455F (7.25C). Under both of the above conditions, defrost will end after 10 minutes. If Alarms 138 and 12000 are also both active: alarm and defrost will not be allowed.

Auto Reset when 3DTT is in range or, alarm may be manually reset via keypad or by turning the unit off, then back on again.