TM 5-4520-253-13
REMOVE/INSTALL PC BOARD ASSEMBLY (CONT)
lNSTALLATiON:
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14.
Install PC board using four screws (73) and lock washers (74) and two screws (71) and lock washers (72).
Thread wires (21, 22,24,26,32, and 33) down through hole in exchanger housing panel. For Model UH-68G,
thread wires (38, 39,41,42,44, and 45) down through hole in exchanger housing panel. Press grommet (58)
into place.
When connecting wires, always connect like colored wires
to each other, e.g., connect red wire to red wire, white wire
to white wire.
Locate oombustion blower (68) on the left-hand side of heater. Connect yellow wire (69) and white wire (70)
to wires of combustion blower.
Connect red wire (63) to red wire of ventilating air motor (64). Connect white wire (67) to capacitor (66).
Place boot (65) over terminal of capacitor.
Connect yellow wire (60) and white wire (61) to wires of transformer (62).
Install new tie wraps (59) as shown.
NOTE
Steps 7 through 14 apply for Model UH-68G only.
Thread wires (36, 39,41,42,44, and 45) through opening in flame switch and bracket assembly. Press
grommet (47) into opening.
Connect red and violet wires (41 and 42) to flame switch (43). Connect red and brown wires (44 and 45) to
flame switch (46).
Connect yellow and grey wires (38 and 39) to upper overheat thermostat (40).
Install flame switch and bracket assembly (35) in opening in heater bulkhead. Attach assembly to bulkhead
using two screws (36) and lock washers (37). With screws loosened, adjust flame switch and bracket assem-
bly downward as far as it will go. This seats flame switches ‘(43 and 46) against the heat exchanger. Tighten
screws (36).
Thread red/white and grey wires (32 and 33) through hole in bracket (28). Press grommet (34) into hole,
Connect red/white and grey wires (32 and 33) to lower overheat thermostat (31 ).
Install thermostat (31 ) through mounting hole in heater bulkhead and secure thermostat mounting bracket (28)
using two screws (29) and lock washers (30).
Connect green and blue wires (21 and 22) to fuel solenoid (23). Connect orange wire (24) to carburetor ther-
mostat (25). Connect white wire (26) to carburetor heater (27).
Change 2
4-19
8.
