TM 9-4120-401-14
DIRECT SUPPORT TROUBLESHOOTING - continued
Table 5-1.
MALFUNCTION
TEST OR INSPECTION
C O R R E C T I V E ACTION
Use great care to avoid contact with liquid refrigerant or refrigerant gas being
discharged from any container under pressure. Sudden and irreversible tissue
damage can result from freezing. Wear thermal protective gloves and a face
protector or safety glasses in any situation where skin or eye contact is possible.
Prevent contact of refrigerant gas with flame or hot metal surfaces. Heat causes
the refrigerant to break down and form carbonyl chloride (phosgene), a highly
toxic and corrosive gas.
AIR CONDITIONER OPERATES CONTINUOUSLY ON COOLING CYCLE.
Step 1. Check position of potentiometer TEMPERATURE control. (See paragraph 2-2.)
Move control to WARM.
Step 2. Check potentiometer TEMPERATURE control. (See paragraph 4-27.)
Replace if defective.
Step 3. Check solenoid valve. (See paragraph 5-25.)
Replace if defective.
6. SIGHT GLASS APPEARS YELLOW INSTEAD OF GREEN.
Step 1. Sight glass appears yellow.
Replace refrigerant desiccant dehydrator. (See paragraph 5-22.)
Step 2. Run unit for one hour and check for yellow sight glass.
Replace refrigerant desiccant dehydrator and re-check. (See paragraph 5-22.)
AIR CONDITIONER NOISY DURING OPERATION.
Step 1. Check expansion valve. (See paragraph 5-24.)
Replace if defective.
Step 2. Check compressor for internal noise and loose mounting. (See paragraph 5-33.)
a. Repair loose mounting.
b. Replace compressor if defective.
5-5
