TM 5-4520-253-13
Table 4-1. Intermediate Maintenance Troubleshooting
Death or serious injury could occur if precautions are not
taken when maintaining this equipment. Position HEATER-
OFF-FAN switch to OFF, remove power cable plug from
POWER RECEPTACLE, and ground capacitors C1 and C2
prior to gaining access to heater compartments. Terminals
of capacitors are accessible at end cover of combustion
blower. Always disconnect power cable before making con-
tinuity tests or before repairing heater. Always have
another person standing by who is trained in electric shock
first aid.
Remove electrical charge from ventilating air motor capaci-
tor C3 by shorting out contacts using tool having insulated
handle.
Allow sufficient time for heater to cool to room tempera-
ture before gaining access to heater compartments.
NOTE
All procedural instructions assume that appropriate access
openings have been uncovered to perform the procedure
described. Access to heater compartments is achieved as
follows:
Open left door (1), front access door (2), and
right door (3) by unlocking one stud (4) at
each door. Open control box cover (5) by
unlocking one stud (4).
Remove six screws (6) and lock washers (7)
and lift off bottom cover (8). Reach through
heater case opening (9) and disconnect louver
linkages from louvers.
Remove right-hand louver panel (10) and
left-hand louver panel (11) by unlocking
eight studs (12) at each panel.
4-2
