DESCRIPTION AND USE OF OPERATOR CONTROLS AND INDICATORS

TM 9-4120-428-14

OPERATOR'S MAINTENANCE

AIR CONDITIONER, HORIZONTAL, COMPACT

(NSN 4120-01-502-1319)

DESCRIPTION AND USE OF OPERATOR CONTROLS AND INDICATORS

GENERAL

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.

NAME

FUNCTION

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

Louver

louver blades.

Return Air Louver

Can be adjusted to control the amount of air being circulated in the shelter. For optimum

Assembly

performance, the louvers should be fully open.

Fabric Cover

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.

Temperature Selector

A toggle switch used to select either of two fan speeds depending on shelter requirements.

Compressor Circuit

Provides compressor electrical circuits overload protection. Will automatically trip off if

Breaker

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

Cutout Switch

(suction) side of refrigerant system drops to switch setting. If tripped, it must be manually

reset.

High Pressure Refrigerant

Provides high-pressure operation protection. Will automatically trip open if high-pressure

Cutout Switch

(discharge) side of refrigerant system rises to switch setting. If tripped, it must be manually

reset.

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.

0004 00-1