Table 4-2. Organizational Troubleshooting

TM 5-4120-386-14

Table 4-2. Organizational Troubleshooting-Continued.

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

1. AIR CONDITIONER FAILS TO OPERATE - Continued

Check to see whether control or compressor circuit breaker is in OFF

Step 6.

position or is defective.

Make continuity check with ohmmeter. Reset circuit

breaker. (Refer to paragraph 4-25.7.)

Disconnect control circuit transformer and make continuity check of

Step 7.

primary and secondary windings, and from windings to case, using

ohmmeter. Reset circuit breaker.

If windings do not show continuity, or if windings-to-case

continuity exists, replace transformer. (Refer to paragraph

Step 8. Apply 30-volt AC to input side terminals of control circuit rectifier,

and check to see that 24-28 volts DC exists at end terminals.

Replace bad rectifier. (Refer to paragraph 4-28.)

2. INSUFFICIENT COOLING

Step 1.

Check to see that mode selector switch is properly positioned.

Step 2. Check liquid sight indicator level to see that refrigerant is colorless and

clear. Yellow indicates moisture in system. Milky or bubbly

refrigerant indicates low level refrigerant charge.

Report condition to direct support maintenance personnel.

Inspect condenser coil for dirt.

Step 3.

Compressed air used for cleaning purposes will not exceed 30 psi (2.1

k g / c m2). Do not direct compressed air against skin. Use goggles or full

face shield.

Clean coil with 25-30 psi (1.76 -2.11 kg/cm2) compressed air.

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