Thermo King T-1000R, Maintenance Manual

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Operating Instructions Standard HMI 7-12
Initiating a Manual Defrost Cycle
Defrost cycles are usually initiated automatically based on time or demand. Manual defrost may also be available. Defrost is
only available if the unit is running and the evaporator coil temperature is less than 7 C. Other features such as door switch
settings may not allow manual defrost under some conditions.
To initiate a manual defrost cycle, press the DEFROST Key (See Figure "Standard Display" page 6). If conditions allow, the
unit will enter a defrost cycle and the amber LED next to the DEFROST Key will glow.
Initiating a Zone Manual Defrost Cycle
From the Standard Display, press the Enter Key to put the unit in Manual Zone Selection mode. Press the Enter Key again as
required to select the desired zone. To initiate a manual defrost cycle, press the DEFROST Key. If conditions allow, the unit will
enter a defrost cycle and the amber LED next to the DEFROST Key will glow.
Important: During the defrost cycle, the box temperature will rise toward 50 F (10 C). This is normal and is caused by the defrost cycle
warming the evaporator coil. Since the damper door is closed during the defrost cycle, this warm air is not allowed to pass into the
truck box.
Box temperature will rise toward 11C
Terminating a Defrost Cycle
The defrost cycle terminates automatically when the coil temperature is greater than or equal to 11 C or the maximum defrost
timer expires. Alarm code 14, Defrost Terminated by Time, will generate if the maximum defrost time is exceeded. When the
defrost cycle is completed the amber LED next to the DEFROST Key will turn off. Defrost can also be terminated by turning
the unit off and back on.