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Air Conditioning And Heater
Air Conditioning And Heater Operation
To turn on the Air Conditioning, set the fan control at any
speed and press the snowflake button located at the right
of the control panel. Conditioned air will be directed
through the outlets selected by the mode control. A lightin the snowflake button shows that the air conditioning is
on. Press the button a second time to turn the air
conditioning off.
Slight changes in engine speed or power may be noticed
when the air conditioning compressor is on. This is a
normal occurrence as the compressor will cycle on and
off to maintain comfort and increase fuel economy.
The mode control (at the right of the
control panel) can be set in any of the
following positions:
NOTE:To improve your selection choices, the system
allows you to operate at intermediate positions between
the major modes. These intermediate positions are iden-
tified by the small dots.Mode Control
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Recirculation Modes (Panel or Bi-Level)
Select the recirculation modes when
the outside air contains dust, odors,
high humidity, or if rapid cooling is
desired. This feature allows for recir-
culation of interior air only. Air flows
through the panel outlets in this mode.
Panel (Fresh Air Modes)
Outside air flows through the outlets located in the
instrument panel.
Bi-Level
Outside air flows through the outlets located in the
instrument panel and at the floor.
Floor
Outside air flows primarily through the floor out-
lets located under the instrument panel.
Mix
Outside air flows in equal proportions through the
floor and defroster outlets.
Defrost
Outside air is primarily directed to the windshield
through the defroster outlets located at the base of
the windshield, and the demister outlets located at the
edge of each side of the instrument panel.
Blower Control
The rotary knob on the left of
the control panel is the
blower control. Turn the knob
clockwise to one of the four
positions to obtain the blower
speed you desire.
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Temperature Control
The rotary knob at the center
of the control panel controls
the temperature of the inte-
rior air. You can choose your
degree of comfort by rotating
the knob. The coldest tem-
perature setting is to the ex-
treme left (blue region) and
the warmest setting is to the
extreme right (red region) of
the rotation.
Circulation
The cab is designed with features to promote outside air
circulation. There are grilles in the cab back panel. These
are air exhausters that provide the means for regular
exchange of cab air.Side window demisters direct air flow specifically to the
window glass to help prevent interior fogging of the
glass. They are located in the extreme outside upper
edges of the instrument panel. The demisters also pro-
vide extra air ducts for circulation. They are in operation
whenever the Floor, Mix or Defrost modes are in use.
NOTE:When you turn off the engine you may hear a
hissing sound from under the hood for a short period of
time. This is a normal condition that occurs if the air
conditioning system has been on. It is not an indication of
a problem with the air conditioning system.
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Operating Tips
Fast Cooldown
For a fast cooldown, turn the blower fan rotary knob to
the extreme right position, turn the mode control to the
panel fresh position, press the snowflake button to turn
on the air conditioning, and drive with the windows
open for the first few minutes. Once the hot air has been
expelled, close the windows and turn the mode selector
to the Recirculation Panel Mode or Recirculation Mode
Bi-level position. When a comfortable condition has been
reached, choose a mode position and adjust the tempera-
ture control knob and blower speed as necessary to
maintain comfort. For high humidity conditions it may
be necessary to remain in the Recirculation mode to
maintain comfort.
Window Fogging
Windows will fog on the inside when the humidity inside
the vehicle is high. This often occurs in mild or cooltemperatures when it’s rainy or humid. In most cases
turning on the Air-conditioning (pressing the snowflake
button) will clear the fog. Adjust the temperature control,
air direction and blower speed to maintain comfort.
As the temperature gets colder it may be necessary to
direct air onto the windshield by using MIX Mode
position on the control. Adjust the temperature control
and blower speed to maintain comfort. High blower
speeds will reduce fogging. Interior fogging on the
windshield can be quickly removed by selecting the
defrost mode.
Regular cleaning of the inside of the windows with a
non-filming cleaning solution (vinegar and water works
very well) will help prevent contaminates (cigarette
smoke, perfumes, etc.) from sticking to the windows.
Contaminates on the inside of windows can increase the
rate of window fogging.
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Summer Operation
Air conditioned vehicles must be protected with a high
quality antifreeze coolant during summer to provide
proper corrosion protection and to raise the boiling point
of the coolant for protection against overheating. A 50%
concentration of engine coolant to distilled water is
recommended. See coolant section of Owner’s manual.
When using the air conditioner in extremely heavy traffic
in hot weather especially when towing a trailer, addi-
tional engine cooling may be required. If this situation is
encountered, operate the transmission in a lower gear.
When stopped in heavy traffic, it may be necessary to
shift into NEUTRAL and depress the accelerator slightly
for fast idle operation.
Winter Operation
When operating the system during the winter months,
make sure the air intake, located directly in front of the
windshield, is free of ice, slush, snow, or other obstruc-
tions.
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Operation Tips Chart
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REAR WINDOW DEFROSTER – IF EQUIPPED
CAUTION!
Use care when washing the inside of the rear win-
dow to prevent damage to heating elements. Use a
soft cloth and a mild washing solution, wiping
parallel to the heating elements. Also, keep all
objects a safe distance from the window to prevent
damaging the heating elements.
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