TM9-4120-400-14
l. After 15 minutes of operation check the sight glass to determine the refrigerant condition. 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 a 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 for appropriate refrigeration system action.
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.
m. Turn the MODE SELECTOR switch to OFF. Observe that all air conditioner functions cease.
2-7. GENERAL OPERATING PROCEDURES.
The Model F9000H-3SA and F9000H-1SA air conditioners are designed for operation in a wide range of climatic
conditions either continuously or intermittently. The amount of operator attention required will vary depending on
specific local conditions for each installation. Under usual conditions, the air conditioner will be set up for the
appropriate mode of operation at the beginning of a season and will only need starting and stopping and minor
adjustments for the rest of the season. Table 2-2 provides the recommended initial control settings to establish
the desired mode of operation. Minor adjustments maybe required to obtain the desired mixture of recirculated
and fresh air and the airflow patterns of conditioned air.
NOTE
Under some climatic conditions, local practices may be established to close the fresh air
damper and/or roll down and snap in place the fabric cover during shutdown periods. If
such practices are in effect, the operator must first unsnap, roll up, and secure the fabric
cover and appropriately adjust the fresh air damper before turning the MODE SELECTOR
switch to the desired operating mode.
2-10