Chevrolet Light Duty Truck 1973 Service Manual page 27

Standard H eater.............................................................................. 1A-1
Auxiliary H eater.............................................................................. 1A-14
Air C onditioning............................................................................. 1A-18
General Description........................................................ 1A-1
Theory of Operation....................................................... 1A-3
System Components....................................................... 1A-3
System Controls............................................................... 1A-3
Component Replacement and R ep air...................... 1A-4
Blower M otor................................................................... 1A-4
Heater Distributor and Core Assembly................. 1A-4
Heater Hoses.................................................................... 1A-5
Heating components are attached to the dash panel on
the right side of the vehicle. The blower and air inlet
assembly and water hoses are located on the forward
side of the dash panel while the heater core and
distributor duct are on the passenger side.
The heater system is an air mix type system in which
SECTION 1A
HEATER AND AIR CONDITIONING
CONTENTS OF THIS SECTION
STANDARD HEATER
GENERAL DESCRIPTION
Fig. 1A--Heater A ir Flow Schematic G Models
HEATER A N D AIR C O N D IT IO N IN G
INDEX
Center Distributor Duct - G M odels..................... 1A-5
Left Distributor Duct - G M odels......................... 1A-6
Defroster D uct................................................................ 1A-6
Control Assembly........................................................... 1A-7
Control Cables................................................................. 1A-7
Blower Switch................................................................... 1A-9
Resistor U nit.................................................................... 1A-9
Diagnosis............................................................................. 1A-10
outside air is heated and then mixed in varying amounts
with cooler outside air to attain the desired air
temperature. The system consists basically of three parts:
(1) the blower and air inlet assembly, (2) the heater
distributor assembly and (3) the heater control assembly.
1A-1
LIGHT DUTY TRUCK SERVICE MANUAL