Peterbilt Model 320 Operator's Manual after 8-07 - Peterbilt Motors ...

PART 4: CONTROLS AND DISPLAYS
Heating And Air Conditioning Controls
WARNING! Do not drive with visibility reduced
by fog, condensation, or frost on the windshield.
Your view may be obscured, which
could result in an injury accident. For clear visibility
and safe driving it is extremely important
for you to follow the instructions pertaining to
the function and use of the ventilation/heating
and defogging/ defrosting system. If in doubt,
consult your dealer. Maximum heating output
and fast defrosting can be obtained only after
the engine has reached operating temperature.
CAUTION: During extreme cold weather, do not
blow hot defroster air onto cold windshields.
This could crack the glass. Turn the air flow
control lever to Defrost and adjust the fan speed
accordingly while the engine warms. If the engine
is already warm, move the temperature selector
to Cool, then gradually increase the temperature
when you see that the windshield is
starting to warm up.
CAUTION:
• A cold compressor can cause refrigerant to
liquefy and warp the valve plates or cause a
hydraulic lock. Warm the engine before starting
the air conditioner.
• To avoid damage to the compressor & blower
motors, turn off all controls when a system is
not in use.
NOTE: Air registers are located on both sides of the
cab. They may be positioned to clear (defrost) the
side windows. Closing these nonwindshield registers
may help to defrost the windshield quicker.
• To defrost the windshield, select the "Defrost” mode
and the desired air source, then set the air temperature
lever to “Hot” and the blower speed to “High.” [Note: If
yourvehicleisequippedwitharoofmountedairconditioner,
turn the air conditioner switch on.] When the
windshield is clear, adjust the temperature and blower
speed until comfortable.
R(08/07) Y53-6015 – 39 –