TM 9-4120-411-14
Section III. OPERATION UNDER USUAL CONDITIONS
2.3 ASSEMBLY AND PREPARATION FOR USE.
2.3.1 Notify unit maintenance personnel and refer them to service upon receipt instructions contained in Chapter 4,
2.3.2 Perform all of the PMCS procedures listed in table 2-1.
2.4.1 General.
2.4.1.1 Check that ducts (1) have been connected between the FDECU and shelter, also that they are secure and not
kinked. Ducts should be fully extended with the least number of bends as possible. Sharp bends, kinks, or collapsed
ducts will restrict airflow and lower unit performance.
WARNING
Rotating parts are used in operating the FDECU. Do not install or adjust return air
duct when inside blower is operating. The flange assembly can disengage and
come off resulting in personal injury.
NOTE
Fresh outside make-up air is recommended during normal operating conditions.
2.4.1.2 Check that the duct (1), connected to the FDECU return air flange assembly (2), was installed back on the flange
assembly far enough to expose the perforated holes as necessary. To assure a continuous supply of fresh make-up air,
at least four or five rows of perforated holes should be exposed.
2.4.1.3 Check that the drain hose (3) has been brought out of the FDECU and will drain in an appropriate area away from
the unit.
2.4.1.4 If the remote control panel (4) is to be used, check that it has been mounted inside the shelter and that any
openings made in the shelter to route it have been sealed.
2.4.1.5 Check that the FDECU cover (5) is down and secured by the latch hinges (6).
2.4.1.6 Release fasteners then open the fan cover door (7) and secure with quick release pin (8).
2.4.1.7 Check that the FDECU power cable (9) has been connected to a power source.
NOTE
(FDECU-2 ONLY) The compressor crankcase temperature lockout could prevent
the compressor from operating immediately. If the compressor is to operate,
power must be connected to the unit for approximately three hours. This is to
raise the compressor temperature above the surrounding ambient air temperature.
(FDECU- 2 ONLY) (FOR AIR FORCE ONLY) On some FDECU- 2 units, the
compressor crankcase sensor has been bypassed to eliminate the compressor
warm up delay. This is accomplished by installing a jumper or splice in the
harness that will connect the crankcase sensor (CCS) and common (COM)
terminals of terminal block (TP4) on circuit board (A2A1).
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