Section I. DESCRIPTION AND USE OF OPERATOR'S CONTROLS AND INDICATORS
2-1. GENERAL. The Model 3863 Air Conditioner is designed for a variety of installations
and for operation under a wide range of climatic conditions. It is also designed for continuous
or intermittent operation as a self-contained unit or may be connected to or used with external
filtering equipment for operation under nuclear, biological, chemical (NBC) environmental
conditions. Operators must be aware of any peculiarities or operational limitations for their
specific installation. See the appropriate shelter or system manual for instructions peculiar to
your specific installation.
OPERATOR'S CONTROLS. See Figures 2-1
for a general description
controls that an operator will normally be concerned with. For specific operating instructions,
see Sections III and IV of this chapter.
INDICATORS. The refrigerant sight glass (Refer
to Figure 2-2)
is the only visual indicator
used on the Air Conditioner. The sight glass is a port or window through which the refrigerant
condition can be seen. Liquid refrigerant actually flows though 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 of
refrigerant at sight glass. The sight glass is equipped with a center indicator 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 appearance, 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.
Do not operate the air conditioner in the COOL mode if the
refrigerate color has reached the yellow bank 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.