TM 9-4120-403-14
TABLE 4-2. UNIT TROUBLESHOOTING
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
1. AIR CONDITIONER DOES NOT START IN ANY MODE.
Step 1. Make sure that power is 115 Volt, single phase, 50/60 hertz.
Connect correct input power.
Step 2. Check operation of the circuit breaker external reset control
Test reset control. (See para 4-34.) Replace if defective.
Step 3. Check operation of mode selector switch (S).
Test switch. (See para 4-27.) Replace switch, if defective.
Step 4. Check all terminals and internal wiring within junction box for tightness and damage.
Tighten terminals, or repair wiring as necessary. (See para 4-47.) If malfunction still
exists, notify your supervisor.
2. COMPRESSOR DOES NOT START, BUT FAN MOTOR OPERATES IN HI- AND LOW-SPEED.
Step 1. Check operation of time delay relay (K6).
Test relay. (See para 4-38.)
Step 2. Check operation of compressor motor relay (K1).
Test relay. (See para 4-36.) Replace relay if defective.
Step 3. Check operation of armature relay (K10).
Test relay. (See para 4-52.) Replace if defective.
Step 4.
Check operation of compressor run capacitor (C2).
Test capacitor. (See para 4-51.) Replace if defective.
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