TM 5-4310-375-14
CAUTION
When installing the heater coils (14) make certain all three overload
relay indicators are set in the "H" position as shown in Sketch "E. "
(6) Install the three heater coils (14) as shown in Sketch "E."
(7) Assemble the motor starter assembly (9) to mounting panel (8) and secure with three screws (7), lockwashers
(6) and nuts (5). Install starter and panel assembly in control box (31); secure with four screws (4).
(8) Install ON-OFF switch (2) and legend plate (3). Install the reset button (1).
(9) Make all wiring connections as tagged at disassembly. Refer to figure 1-2 for wiring diagram.
4-16. Motor assembly. Maintenance of motor assembly is as follows:
Electricity is dangerous. Before performing any maintenance or adjustments,
be sure the electrical power is turned off. Never depend on the ON-OFF switch.
Turn power off at the source.
a. Inspection/Test. Turn ON-OFF switch on motor control box to OFF position. Turn main power source off.
Remove four screws (1, fig 4-4) securing the motor conduit box lid (2) to the conduit box (7). Remove the lid (2) and
gasket (3). Inspect the motor lead connections with nameplate (11) on side of motor. These connections shall be for
230 volts, three phase, 60 hertz. Examine leads for evidence of shorts or grounds and for burned lead insulation. Open
motor control box door and check for proper connection of motor leads to starter terminals. Refer to figures 4-1 and 1-2.
Remove cover of pressure switch and examine for loose connections and for defective switch. If all wiring connections are
secure and correct, wires or switch are not damaged, and motor still does not operate, the motor assembly shall be replaced.
b. Removal. Remove motor assembly as follows:
(1) Disconnect motor leads T1, T2, and T3 inside motor conduit box (7, fig 44). Remove conduit connector (4)
and two conduit reducing washers (5) from motor conduit box (7), pulling wires out of conduit box.
(2) Refer to para 4-14 and remove belt guard, drive belts and drive pulley.
(3) Unscrew and remove four locknuts (8), flat washers (9) and screws (10). Attach a lifting device to lifting eye on
top of motor assembly (12) and remove motor assembly.
c. Repair or Replacement. Notify Direct Support for repair requirement of motor assembly.
d. Reassembly. Reassemble a new or repaired motor assembly onto unit in following sequence.
(1) Install motor assembly (12, fig 4-4) on air receiver and reassemble the four mounting screws (10), flat
washers (9), and locknuts (8) but do not tighten hardware until drive belts are installed and pulleys are aligned.
(2) Refer to para 4-14 and reassemble drive pulley, install drive belts, align and adjust belts as instructed in
(3) Reconnect conduit (6, fig 4-4) to conduit box (7) with two conduit reducing washers (5) and connector (4).
4-14
