Chevrolet 10 1971 Series Chassis Service Manual page 28

HEATER AND AIR CONDITIONING 1A-10
HIGH PRESSURE LINE
C OM PRESSOR
RECEIVER DEHYDRATOR
inner and outer body panels on the left hand side of the
vehicle as shown in Figure 16.
This system differs from the Four-Season System in
that refrigerant flow is split between two expansion
valves and follows separate piping through the evaporator
core before flowing back into one line after leaving the
core.
CONTROLS
Operation of the system is controlled from a single
overhead knob located in a recessed portion of the central
distribution duct (fig. 17). In the OFF position the system
is totally inoperative. In any of the other three positions
(LO, MED, or HI) the compressor and the air conditioning
blower motors are operative.
When operating the air conditioning
NOTE:
system, the heater controls should be in the OFF
position to obtain maximum cooling.
G M CHEVROLET SYSTEM
The GM Chevrolet System is available as a dealer -
installed accessory for CIO-30 and K10-20 series trucks.
This system is also similar to the Four-Season System
in placement of the compressor, condenser and receiver-
AIR DUCT
CONTROL KN OB
Fig. 16— Roof Mounted System Components
LOW PRESSURE LINE
dehydrator (fig. 18). It differs from the Four-Season Sys­
tem in that it:
1. Operates independently of the heater system.
2. Operates on recirculated (inside) air only.
3. Utilizes a thermostatic switch instead of an evap­
orator control (POA) valve to control outlet air
temperature.
Fig. 17— Roof Mounted System Controls
EVAPORATOR
D RA IN HOSE
10-30 CHEVROLET TRUCK SERVICE MANUAL