TM 9-4120-407-14
Control Panel Assembly Fault Indicator Lights.
(1) The TEMPERATURE/PRESSURE FAULT indicator will come on if either of the evaporator fan
motors or condenser fan motor exceed safe operating temperature. The light will also come on if any of the
following switches opens, thermostatic (heater cutout), coil frost, low pressure cutout, or high pressure
cutout.
(2) The OVER CURRENT FAULT indicator light will come on if the motor controller draws
excessively high amperage.
(3) The OVER/UNDER VOLTAGE FAULT indicator light will come on if the motor controller
receives excessively high or low voltage.
(4) The HOT MOTOR CONTROLLER FAULT indicator light will come on if the motor controller is
exposed to excessively high temperatures.
2-3.
a . Fresh Air Damper Control Knob. The fresh air damper control knob is located on both the front and
rear of the air conditioner and allows fresh air to be introduced into the system.
b. The High Pressure Cutout. The indicator is located in the rear of the air conditioner and has a manual
reset button. The Temperature/Pressure indicator light on the control panel will come on if the refrigerant
discharge pressure exceeds safe operating limits causing the switch to trip.
c. The Liquid Sight Indicator. The liquid sight indicator has a small chamber with a glass window
through which the refrigerant flow can be observed. The liquid sight indicator is equipped with a center
indicator that is moisture sensitive.
d. The Condenser Discharge Air Deflector Door. The condenser discharge air deflector door must be opened
during cooling operation to allow discharge air to vent.
e. Mode Selector Rotary Switch. The MODE selector rotary switch is located on the control panel and
allows the user to set the desired mode such as HEAT, VENT, COOL and OFF/RESET by turning the knob.
f . Temperature Control Potentiometer. The temperature control potentiometer is located on the control
panel and is used to adjust the level of cooling or heating. This is accomplished by turning the knob
clockwise to increase or counterclockwise to decrease temperature.
g. Evaporator Air Discharge Grille Louvers. The grille louvers allows the conditioned air to circulate and
be directed throughout the room or enclosure.
h . Evaporator Air Return Grille Louver Handles. These control levers allow the user to adjust the air
intake.
2-4
