TM 9-4120-371-14
Section V TROUBLESHOOTING
a. This section contains troubleshooting information for location and correcting most of the operating
troubles which may develop in the air conditioner unit. Each malfunction for an individual component, unit, or
system is followed by a list of tests or inspections which will help you to determine corrective actions to take.
You should perform the tests/inspections and corrective actions in the order listed.
b. This Manual cannot list all malfunctions that may occur, nor all tests or inspections and corrective
actions. If a malfunction is not listed, or is not corrected by listed corrective actions, notify your supervisor.
c. Table 4-2 lists the common malfunctions which you may find during the operation or maintenance of the
air conditioner unit or its components. You should perform the tests/inspections and corrective actions in the
order listed.
NOTE
Before you use this table, be sure you have performed all applicable operating checks.
HIGH VOLTAGE
is used in the operation of this equipment.
DEATH ON CONTACT
may result if personnel fail to observe safety precautions.
Never work on electrical equipment unless there is another person nearby who is familiar
with the operation and hazards of the equipment and who is competent in administering
first aid, When the technician is aided by operators, he must warn them about dangerous
areas.
Whenever possible, the input power supply to the equipment must be shut off before
beginning work on the equipment. Take particular care to ground every capacitor likely to
hold a dangerous potential. When working inside the equipment, after the power has been
turned off, always ground every part before touching it.
Be careful not to contact highvoltage connections of 208 volts ac input when installing or
operating this equipment.
Whenever the nature of the operation permits, keep one hand away from the equipment to
reduce the hazard of current flowing through vital organs of the body.
Do not operate the equipment without all grilles, guards, louvers, and covers in place and
tightly secured.
Warning: Do not be misled by the term "low voltage." Potentials as low as 50 volts
may cause death under adverse conditions.