PREVENTIVE MAINTENANCE HEATER AND AIR CONDITIONER
Regional Haul
(R05/10) Y53-6033 – 211 –
• Do not permit any open flame in the area.
Even a match or a cigarette lighter may gen-
erate a hazardous quantity of poisonous
gas.
• Do not smoke in the area. Inhaling gaseous
refrigerant through a cigarette may cause
violent illness.
Heater
• Check all heater controls for full-range operation.
• Check hoses, connections, and heater core for condi-
tion and leaks.
• Check the drain pan of the fresh air vent for trapped
water before assuming that there is a leak in the heat-
ing system. If the heater core is leaking, a reliable
radiator shop should be able to repair it.
• Check the heater core for debris blocking the air flow.
If the blower and air controls are functioning properly,
yet the heater is not operating properly, the heater
core or the hot water valves may be clogged or
closed. Clean the heater core if necessary. If the con-
dition persists, take the vehicle to a Peterbilt Dealer
for proper heater service or repair.
CAUTION: During extreme cold weather, do
not blow hot air onto cold windshields. This
could crack the glass. Turn the air direction
lever to Defrost and reduce the fan speed
while the engine warms. If the engine is
already warm, move the temperature selector
to Cool, then gradually increase the tempera-
ture when you see that the windshield is start-
ing to warm-up.
Air Conditioner
WARNING! The air conditioning system is
under pressure. If not handled properly dur-
ing servicing, it could explode, causing death,
injury to you or damage your vehicle. Any ser-
vicing that requires depressurizing and
recharging the air conditioning system must
be conducted by a qualified technician with
the right facilities to do the job.
• Check the compressor and drive clutch for noise and
vibration. If you find problems, have the system
checked thoroughly. A malfunctioning clutch usually
indicates trouble elsewhere in the system.
• Check the evaporator core and condenser core for
debris restricting air flow. Clean if necessary. Small
