TM 9-4120-407-14
1-10. LOCATION AND DESCRIPTION OF MAJOR COMPONENTS. (Cont)
Condensate Water Drip Pan and Drain Trap (22). The drip pan is located below the evaporator coil
and mist eliminator and is built into the casing. Its purpose is to collect condensate that drips off the
evaporator coil and mist eliminator during cooling operations. Condensate water then follows through
tubing to the drain trap located inside the lower right hand front corner of the cabinet. The drain trap is a
check valve that prevents air flow between the condenser and evaporator sections through the drain tubing
Electrical Components Panel (23). Houses the majority of the air conditioner' electrical control
s
components.
Compressor (24). Pumps refrigerant through the system during the cooling operations.
Logic Box Assembly (25). Operates the motor controller and relays for selected operating mode.
Receives status signals from high and low refrigerant pressure switches, motor thermal overloads, air
heater thermostat, and coil frost switch to provide safety shut down of the motor controller if any of these
faults occur.
Motor Controller (26). Controls power to the air conditioner motors as directed by the logic box
assembly. The motor controller uses a "soft start" method to operate the air conditioner motors. This
feature starts the motors on a low voltage and frequency and brings them up to speed at full voltage and
frequency within two seconds. The motor controller also provides power for logic box assembly operation and
reacts to fault signals received by the logic box assembly to provide safety control for the air conditioner
components.
Condenser Air Fans and Motor Assembly (27). Draws air through the condenser coil and discharges
the heated air back to the outside during cooling operations.
Fresh Air Damper Control (28). Provides manual adjustment for fresh air mixture.
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