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4-44
Replacing the
µµ
P-D Controller
µ
P-D Controller
CRR-20 & CRR-40, September 1999
Replacing the
µµ
P-D Controller
CAUTION: When replacing a controller, correct unit
operation requires that the Unit Configuration, Cus-
tomer Configuration and programmable Sensor Grades
be set to the UNIT specific features and sensors.
A replacement controller contains default settings that allow it
to function when installed in a unit. However, CORRECT unit
operation REQUIRES that the Unit Configuration, Customer
Configuration and programmable Sensor Grades be set to the
UNIT specific features and sensors. If this information can not
be recovered from the previous controller, see the unit config-
uration and sensor grade information on the set up decal locat-
ed on the control box door. Then program these settings
before releasing the unit for service. See “Menu Guard” sec-
tion for instructions on programming the controller.
There are many other programmable features that may
need to be set to completely configure the unit to customer
specifications. Customer requirements may include features
such as the container identification number and unit serial
number. Adjust any additional programmable settings to cus-
tomer requirements before releasing the unit for service.
1.
Write down the Unit Configuration Number, Customer
Configuration Number, Container Identification Number,
Hourmeter settings and Sensor Grades on a blank setup
sheet. Recover as much information as possible from the
previous controller. If the previous controller is non-func-
tional, see the setup decal located on the control box door
for the Unit Configuration Number, Customer
Configuration Number and Sensor Grades. The Unit
Serial Number is located on the Unit Nameplate.
2.
Turn the unit On/Off switch OFF. Then unplug the unit
power cord from the power supply.
3.
Disconnect the wire harness connectors from the back of
the controller.
4.
Remove the screws that secure the controller to the con-
trol box door.
5.
Remove the controller and gasket from the door.
6.
Install the replacement controller and gasket in the door
using the existing hardware.
CAUTION: Do NOT over tighten the mounting
hardware or the controller may be damaged.
7.
Attach the wire harness connectors to the back of the con-
troller.
NOTE: Be certain that all connectors are fully
seated until the connector rings lock.
8.
Plug the unit power cord into the proper power supply.
9.
Turn the unit On/Off switch ON. The unit should start
and the Standard Display should appear on the controller.
CAUTION: Immediately proceed to procedure for
“Setting the Unit Configuration and Customer
Configuration Numbers” in the “Menu Guard” sec-
tion of this chapter. Alarm code 42 should be pre-
sent in the display when the Alarm key is pressed.
This indicates that the correct Unit Configuration,
Customer Configuration and Sensor Grades must
still be set.
Temperature Sensors
All sensors should be properly installed:
• Supply sensor installs in the sensor tube next to the control
box. The sensor must be inserted to the bottom of the sensor
tube and completely sealed by the grommet connection.
• Return air sensor installs in a grommet between the evapora-
tor fans.
• Evaporator coil sensor must be placed in the coil fins
between tube rows 2 and 3 in the middle of the coil.
• Condenser sensor must be placed on the left side of the con-
denser coil and at lest 70 mm deep between the fins.
• Ambient sensor must be placed on the bottom plate of the
right forklift pocket.
• Compressor discharge gas temperature sensor must be placed
in the back side of the compressor head.
Evaporator Coil Sensor Location — Units with Three
Evaporator Fans
A.
Coil Support Brackets
B.
Unit Front
C.
Insert Sensor between Tube Rows 2 and 3
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