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3.2.2
Remote Compartment Set Point Change (SEtPt)
For independent readings of remote set point and supply or return air temperature, use the following steps:
1. Ensure Cd52 is enabled and press the ENTER key.
2. The left display window will display "SEtPt".
3. The right display window will display the present set point.
4. To change the set point, move arrow key up or down until the desired set point is displayed in the left win-
dow. This value will keep flashing, and range from 28.0 to 70.0°F (-2.2 to 21.1°C) in 0.1 degree increments.
5. Press the ENTER key to initiate set point change. If ENTER is not selected, set point will not change.
3.2.3
Remote Compartment Sensor Data
To display sensor readings for the remote air supply air temperature, the remote secondary supply temperature, or
the remote defrost temperature sensor, use the following steps:
1. From Cd52, press the ENTER key to scroll to the desired sensor.
2. The left display windows will display the desired sensor:
PSPLY - Remote Supply Air Temperature
SSPLY - Remote Secondary Supply Temperature
rErUR - Remote Return Air Temperature
dtS - Remote Defrost Temperature Sensor
3. The right display window will display the present sensor reading.
3.2.4
Remote Evaporator SMV Position
The unit is capable of maintaining supply air temperature to within ± 1.8 degrees F (1.0 degrees C) of set point.
Supply air temperature is controlled by positioning of the suction modulation valve (SMV), cycling of the compres-
sor, and cycling of the heaters. Use the following steps to display the remote evaporator RSMV position:
1. From Cd52, press the ENTER key to scroll to the desired sensor.
2. The left display window will display "rESV".
3. The right display window displays the remote evaporator SMV position in 0 - 100 in 1% increments.
3.2.5
Remote Evaporator Defrost Interval
Both compartments will defrost simultaneously if initiated manually by pressing the Manual Defrost interval key for
5 seconds. Both compartments will defrost automatically and independently at the user selected time interval.
Defrost can only occur when DTS is below a set value, indicating that box temperatures are low enough to allow
frost on the evaporator coil. Termination will occur when DTS reaches a set value. If DTS does not reach this value
within 2 hours, the controller will terminate the defrost cycle and an alarm will be activated, indicating that defrost
terminated abnormally.
There are two modes for initiating defrost on the dual temperature platform - either user-selected timed intervals or
manual defrost control. The user-selected values are 3, 6, 9, 12, or 24 hours. The factory default for the timed inter-
val is 12 hours (some units may be configured to allow defrost to be disabled altogether; in this case, a user-
selected value of OFF will be available).
All defrost interval times reflect the number of compressor runtime hours since the last defrost de-ice cycle. The
minimum defrost interval under the automatic setting is three hours while the maximum is 24. In frozen mode, the
amount of wall-clock time necessary to accumulate a given amount of defrost interval time will exceed the defrost
interval time by a factor of two to three depending on the compressor duty-cycle. Defrost interval time is not accu-
mulated in any mode until the defrost termination sensor reads less than the preset value.
To change the remote evaporator defrost interval, use the following steps:
1. From Cd52, press the ENTER key until the left window displays "dFrSt".
T-319
3–4
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