Chevrolet Light Duty Truck 1973 Service Manual page 40

1A-14 HEATER A ND AIR C O N D IT IO N IN G
General D escription...................................................................... 1A-14
Component Replacement and Repairs.................................... 1A-16
Diagnosis........................................................................................... 1A-17
An auxiliary heater is available as a dealer installed
accessory to provide additional heating capacity for the
rearmost extremities of the C-K (06) and G models.
This unit operates entirely independent of the standard
heater and is regulated through its own controls at the
instrument panel.
This system consists of a separate core and fan unit
mounted as shown in Figures 15 and 16.
Heater hoses extend from the unit to the front of the
vehicle where they are connected to the standard heater
hoses with "tees". An "on-off" water valve is installed in
the heater core inlet line in the engine compartment.
This valve must be operated manually—"on" for cold
AUXILIARY HEATER
C ontrols........................................................................................... 1A-14
GENERAL DESCRIPTION
INDEX
weather, "off" in warm weather. The purpose of the
valve is to cut off coolant flow to the auxiliary core
during warm weather and eliminate the radiant heat that
would result.
CONTROLS
Two methods of control are employed with this system:
Water Valve (Fig. 17)
When heat is desired, the water valve must be in the
"on" position (valve located in the engine compartment
LIGHT DUTY TRUCK SERVICE MANUAL