General Refrigerator Terminology; Wiring Diagrams - Dometic CD20 Service Manual

General Information
y
q
3 General CRX Component Locations (Front View)
Door Assembly
q
Shelving and Racks
w
Thermostat Assembly
e
I The NTC sensor is mounted on the interior of the
unit toward the left side of the refrigerator.
4 .4 General Refrigerator
Terminology
The following table defines some of the terms that are
typically used when dealing with refrigerator units.
Term
Refrigerant liquid metering device that
Capillary Tube regulates refrigerant flow from the high-
pressure side into the low-pressure side
Capillary Tube Filter used to prevent particulate from
Strainer/Dryer entering the refrigerant flow control
Component that circulates the
Compressor refrigerant necessary for heat exchange
through the coils
Heat exchanger section to cool down
Condenser and condense incoming refrigerant
vapor into liquid
Tubing used to release heat energy from
Condenser Coil refrigerant and condense refrigerant
vapor into liquid
6
t
e r
w
Vent Cover
r
NTC Sensor
t
Handle Assembly
y
Definition
Term
Fan that circulates air, which helps the
Condenser Fan
condenser unit function properly
Power distribution board and
Control Module compressor controller that directs
incoming power to the unit
Component that disconnects the
refrigerator from the truck electrical
Load Dump
system when DC voltage exceeds
Board
32 VDC (reconnection occurs after the
DC voltage returns to normal)
Selector wheel on the refrigerator
Locking Wheel handle assembly that can be set to
"normal" or "vent" positions
Negative Thermistor that allows the refrigerator to
Temperature stay within a short range of temperatures
Coefficient (NTC) and turn on its cooling cycle when the
Sensor temperature starts to rise
Thin board made of fiberglass,
Printed Circuit composite epoxy, or other laminate
Board (PCB) material on which conductive pathways
are etched or "printed"
Device that controls the cooling system
Thermostat
components and interior temperature of
Assembly
the refrigerator unit

4 .5 Wiring Diagrams

Figures 4 and 5 provide examples of the wiring
specifications for CR and CRX series refrigerators.
I The wiring specifications for CD series refrigerators
are similar to those for the CR series shown below.
Input DC 12/24 V
+ –
Compressor
White
Yellow
Gray
Black
Red
4 CR Series Wiring Diagram
Refrigerators
Definition
Red
Red
Gray
PCB
Black
White
White
White
Fan
–
+
Black AC 250 V
Thermostat
6
White
4
Yellow 3
EN