Chevrolet 70 1969 Series, Shop Manual

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CAB A N D BO DY M O U N T IN G S 1-58
O P E R A T IN G H E A T IN G S Y S T E M O N L Y
All four control knobs are in " O F F " position
when placed to extreme left side of control panel.
" D E F R O S T " knob controls flow of air to the
windshield defroster ducts. With knob all the way
to the right, entire heater output is diverted to the
defroster ducts for defrosting.
" T E M P ." knob sets the air temperature door
in desired position. As knob is moved to right of
panel, the air leaving the system is increased.
Knob can be set at any position to maintain desired
temperature. To direct additional air flow towards
passenger's side of cab, a small door at base of
the blower distributor duct, under the dash, can
be pulled downward.
"A IR " knob controls flow of outside air through
the heater unit. Place knob in extreme right posi­
tion for heating only.
H E A T E R F A N SPEE D is controlled by moving
blower switch lever from left to right positions;
O F F - L O W SPEE D - M E D IU M SPEED - and HIGH
SPEED.
For warm weather ventilation less air condi­
tioning, place "A IR C O N D ." lever, " D E F R O S T "
and " T E M P ." control knobs in extreme left posi­
tions, move "A IR " knob to extreme right position,
then place fan switch lever to desired speed posi­
tion. Ventilation will be directed through heater
outlets and not A / C outlets.
VENTILATION
WARNING-CARBON MONOXIDE
Keep cowl vent air intakes closed when operating in congested
traffic to prevent deadly exhaust gases from entering cab.
Exhaust gases may have strong odors which normally should give
warning of their presence. However, the exhaust gases from some
vehicles may not be so noticeable under certain conditions and the
senses of people react differently. Exhaust gases contain a percentage
of carbon monoxide which is poisonous gas that, by itself, is tasteless,
colorless and odorless.
A IR C O N D IT IO N IN G
COMPRESSOR
- - / 6 - 0 .G M .- 3 9 --------------
l
H
h
__
f
Figure 4 — Air Conditioning Wiring Diagram
CHEVROLET SERIES 70-80 H EAVY DUTY TRUCK SH O P M A N U A L