OPERATION
HEATING, VENTILATING AND DEFROSTING
Defrost
CAUTION: To clear the system of humid air,
operate blowers for 30 seconds at "Hi" speed before
moving "AIR OUTLETS" lever to "DEF".
HEATING To use as a fresh air heater, move "AIR"
inlet control lever to "FRESH". Adjust temperature
This will minimize rapid fogging of the glass, which
"HTR" (HEAT) lever as required to give the desired
can occur if humid air is blown onto a cool windshield.
degree of heat. Full right "HOT" position provides
maximum heat. Move "AIR OUTLETS" control lever as
To improve defroster efficiency, remove ice and/or
desired to control air flow. For MAXIMUM AIR FLOW,
snow from glass area.
move both "FAN" switches to "HI". Switches can be
operated in any speed combination.
FRESH AIR VENTILATION To permit fresh air to
enter directly into the cab, push in air door control (left
ventilator).
To direct fresh air through the heater for distribution
through the cab air outlets, place the control panel
"HTR" lever in the "OFF" position. Move the "AIR" lever
to "FRESH". Move "AIR OUTLETS" lever to direct air
stream as desired.
Adjust blower speed and air
registers for desired air flow. Blowers may be operated
Fresh Air Heat
individually or simultaneously in any available speed
combination.
To use as a recirculating type heater, operate heater
controls in normal manner and move "AIR" inlet control
lever to "RECIRC".
ENGINE BRAKE CONTROL OPERATION
After the engine has reached normal operating
Recirculating Heat
temperature and before starting a trip, position the
manual control switch on the instrument panel to "ON."
DEFROSTING
When the vehicle is in motion, the engine brake
To obtain maximum defrosting, move "HTR" lever to
control is in operation when the operator's foot is
"HOT". Place "AIR OUTLETS" lever at "DEF" and "AIR"
removed from the accelerator pedal.
lever to "FRESH". Adjust blower speeds to provide
desired air flow.
The engine brake may be used in general whenever
decelerating the vehicle is required, such as, descending
To put all air on windshield, move "AIR OUTLETS"
grades, city traffic or approaching traffic lights.
control lever to "DEF", close floor outlet.
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