TM9-4120-370-14
TO35E9-229-1
OPERATING INSTRUCTIONS
Section l. DESCRIPTION AND USE OF OPERATOR'S CONTROLS AND INDICATORS
2-1.
GENERAL
These Air Conditioners are designed for a variety of installations and for operation under a wide range of climatic condi-
tions. They are also designed for continuous or intermittent operation as self-contained units or may be connected to or
used with external filtering equipment for operation under chemical-biological-radiological (CBR) environmental condi-
tions. Operators must be aware of any peculiarities or operational limitations for their specific installation. See the appropri-
ate shelter or system manual for instructions peculiar to your specific installation.
2-2. OPERATOR'S CONTROLS
See Figure 2-1 and Figure 22 for a general description of the controls that an operator will normally be concerned with.
For specific operating instructions, see Section Ill and Section IV of this chapter.
The refrigerant sign glass (Figure 22) is the only visual indicator used. The sight glass is a port or window through which
the refrigerant condition can be seen. Liquid refrigerant actually flows through the sight glass chamber only during cooling
cycles when the air conditioner is in operation in the COOL mode. The unit must be operated approximately 15 minutes
at maximum cooling prior to checking condition or refrigerant at sight glass. The sight glass is equipped with a center indi-
cator that is moisture sensitive. Dry refrigerant is indicated by green, it turns to chartreuse when the moisture content
becomes undesirable, and to yellow when the level becomes unacceptable. Excessive moisture in the refrigerant may
damage or possibly destroy the compressor. If the liquid refrigerant observed in the sight glass has an opaque, milky ap-
pearance, or frequent bubbles appear, the volume of refrigerant is low and the system should be charged. Either moisture
or low charge indications should be reported to direct support maintenance.
CAUTION
Do not operate the air conditioner in the COOL mode if the refrigerant color has
reached the yellow band or if numerous bubbles appear in the sight glass. COOL
mode operation may be continued with the refrigerant color in the chartreuse
band or with only an occasional bubble appearing in the window, but the sight
glass should be rechecked after each four hours of operation to insure that the
condition has not become worse.