TM 9-4120-402-14
Table 4-3. UNIT TROUBLESHOOTING - continued
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
5. REDUCED COOLING CAPACITY. - continued
Step 6. With unit operating in COOL mode, check condition of refrigerant in sight glass.
(1) If color is yellow or a light hue of chartreuse, or if numerous bubbles appear, turn air conditioner
OFF/RESET, and notify supervisor.
(2) If color is green or a dark hue of chartreuse, but has a milky appearance, or more than an occasional
bubble appears, thoroughly clean the condenser intake screen, condenser fan guard, condenser coil,
and entire condenser section to remove all obstructions.
(3) Clean and service, or replace mist eliminator. (See paragraph 4-25.) (4) Clean evaporator coil and
entire evaporator section. (See paragraph 4-50.)
Step 7. Check airflow out of conditioned air (evaporator) discharge grille. If air flow volume is low:
(1)
Adjust conditioned air (evaporator) intake grille louvers.
(2)
Clean and service, or replace conditioned air filter element. (See parraph 4-23.)
(3)
Clean and service, or replace mist eliminator. (See paragraph 4-25.)
(4)
Clean evaporator coil and entire evaporator section. (See paragraph 4-50.)
Step 8. Check CBR filter, if installed. (See paragraph 4-11.)
Clean, replace, or adjust as indicated.
Step 9. Check operation of potentiometer TEMPERATURE control.
Test potentiometer TEMPERATURE control. (See paragraph 4-29.) Replace control if defective.
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