TM 9-4120-398-14
GENERAL OPERATING PROCEDURES
Before operation.
a
(1) Check to see that power cable has been connected to a source of 208/230 volt, three phase, 4 wire, 50/60 hertz
power.
Wait 5 hours before starting air conditioner so that the crankcase heater may drive any Iiquid refrigerant
out of the compressor.
NOTE
The 5-hour warm-up is for initial installation only. If the electrical power to the unit remains connected,
the crankase heater will stay hot and the compressor can be started at any time. Refrigerant gas will
condense in cool compressor crankcase oil. The off must be warm to prevent startup damage to the
compressor. Power interruptions of short duration will not require warm-up time if the compressor
crankcase has not been allowed to cool.
(2) Check that all air inlet (2) and outlet (1) duct openings are clear (figure 2-2).
(3) Check that drains (3) are either open or piped to a satisfactory location with a proper drain system.
(4) Table 2-2 lists the recommended control settings for the desired mode of operation. Minor adjustments may
be made to get the desired mixture of recirculated and fresh air.