WD Catalog 2018

821 / 1003

1-3 G - -
Figure 1-3
The inside cab temperature
will be the same or higher
than the outside tempera-
ture when parked for awhile
with all systems turned off.
Heat Movement
WINTER
20°
SUMMER
100°
32°
70° 80°
120°
20°
0°
CAB
TEMP
100°
HEATER CORE
COOLANT LINE
(PRESSURE)
COOLANT LINE
(RETURN)
COOLANT
(WATER) VALVE
WATER PUMP
MOVES HEAT ENERGY
IN THE COOLANT
CONDENSER
REFRIGERANT
SUCTION LINE
COMPRESSOR
MOVES HEAT ENERGY
IN REFIGERANT
REFRIGERANT
DISCHARGE LINE
EXPANSION VALVE
EVAPORATOR
REFRIGERANT
LIQUID LINES
Figure 1-4
We have used arrows to
show you the direction of
refrigerant and engine
coolant flow in the system.
The key system components
are named. The air condi-
tioner evaporator coil and
condenser, and the heater
core, are the main points of
heat transfer.
Figure 1-4 displays the key components in the HVAC system. The arrows show
the direction of refrigerant flow in the system.