AIR CONDITIONER, HORIZONTAL, COMPACT
DESCRIPTION AND USE OF OPERATOR CONTROLS AND INDICATORS
The Model F9000H-4SPFI air conditioner is designed for a wide variety of installations and for operation under a wide range
of climatic conditions. It is designed for continuous or intermittent operation as a self-contained unit, or may be connected to
external filtering equipment for operation under Nuclear Biological and Chemical (NBC) environmental conditions. Operator
must be aware of any oddities or operational limitations for their specific installation.
Table 3. Operator's Controls and Indicators.
Fresh Air Damper Control
Manually controls the position of the fresh air damper to allow more or less outside fresh air
to mix with conditioned air.
Conditioned Air Supply
Can be used to direct the flow of conditioned air in the shelter by positioning the individual
Return Air Louver
Can be adjusted to control the amount of air being circulated in the shelter. For optimum
performance, the louvers should be fully open.
When rolled down in the heating mode, it reduces heat loss from the shelter and minimizes
dirt and debris from obstructing the condenser coil.
Mode Selector Switch
A rotary switch used to select the various modes of operation as necessary for shelter
requirements or environmental conditions.
A toggle switch used to select either of two fan speeds depending on shelter requirements.
Provides compressor electrical circuits overload protection. Will automatically trip off if
compressor current draw exceeds circuit breaker rating. If tripped, it must be manually reset.
Control Circuit Breaker
Provides control system electrical circuits overload protection. Will automatically trip off if
any component in the control system current draw exceeds circuit breaker rating. If tripped,
it must be manually reset.
Low Pressure Refrigerant
Provides low-pressure operation protection. Will automatically trip open if low-pressure
(suction) side of refrigerant system drops to switch setting. If tripped, it must be manually
High Pressure Refrigerant
Provides high-pressure operation protection. Will automatically trip open if high-pressure
(discharge) side of refrigerant system rises to switch setting. If tripped, it must be manually
Refrigerant Sight Glass
A small chamber with a glass window that provides a visual indication of the liquid
refrigerant as it flows through the system. Liquid refrigerant only flows through the sight
glass in the cooling mode of operation when the shelter temperature rises enough to initiate
a cooling cycle. If the liquid refrigerant observed in the sight glass has a milky appearance
or frequent bubbles appear, the volume of refrigerant could be low and the system may need
to be charged. The sight glass contains an indicator that is sensitive to water moisture. This
indicator changes color in response to the amount of water moisture that may be contained
in the refrigerant. Excessive moisture in the refrigerant may damage or possibly destroy the
compressor. If no moisture is present, the indicator will be green. If the moisture content
becomes undesirable, the indicator will be greenish yellow. If the moisture content becomes
unacceptable, the indicator will be yellow. If a low charge or unacceptable moisture level is
indicated, contact direct support maintenance to take appropriate action.