TM 5-4310-368-14
Section IV. OPERATION UNDER UNUSUAL CONDITIONS
This section contains instructions for obtaining optimum operation under unusual conditions.
2-8.
OPERATING IN UNUSUAL WEATHER
a. Operations in Extreme Cold.
CAUTION
Check hoses and ducts for cracks or other cold weather damage prior to starting compressor.
Keep fuel tank full to minimize moisture condensation.
(1) Service engine and clutch with cold weather oil.
(2) Service compressor with cold weather oil.
(3) Close all access doors except the instrument panel access door.
(4) Use the onboard heater for warming the engine when temperatures are below 0 . To operate heater, turn
F
RUN/OFF/START switch to START and hold several minutes until amber INDICATOR lamp comes on.
Move the switch up to the RUN position. Select either HI (30,000 BTU's) or LO (20,000 BTU's) setting. The
heater will then operate automatically. For extremely low temperatures (to -50 ), allow the heater to operate
F
on the HI position for 30-45 minutes before starting the engine. (Figure 2-1)
NOTE
An alternate method of preheating is to connect a 12-inch diameter duct from an external heater to
the engine cooling air inlet. Open the cooling air inlet door fully, and open the compressor cooling
air door about 2 inches.
(5) Start the engine and operate the compressor using usual procedures.
b. Operation in Extreme Heat.
CAUTION
Do not operate the compressor if the ambient temperature exceeds 125 .
F
(1) Open all cooling air and access doors.
(2) Keep all engine, compressor and compressor heat exchanger cooling fins clean and free of obstructions.
(3) Make sure that cooling air flow is not restricted and that cooling air comes from the coolest possible source.
Avoid having heated air being drawn into the cooling fan.
2-15
