TM 9-4120-402-14
Table 5-1. DIRECT SUPPORT TROUBLESHOOTING - continued.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
6.
SIGHT GLASS APPEARS YELLOW INSTEAD OF GREEN.
WARNING
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 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.
Step 1.
Yellow appearance of sight glass is caused by contamination in the refrigerant.
a.
Release refrigerant. (See paragraph 5-11.)
b.
Remove refrigerant desiccant dehydrator. (See paragraph 5-21.)
c.
Purge system. (See paragraph 5-12.)
d.
Install new refrigerant desiccant dehydrator. (See paragraph 5-21.)
e.
Leak test system. (See paragraph 5-15.)
f.
Evacuate system. (See paragraph 5-16.)
g.
Recharge with refrigerant. (See paragraph 5-17.)
Step 2.
Check for yellow in sight glass after allowing compressor to run for at least 1 hour.
Repeat corrective action in Step 1 above if sight glass is still yellow.
7.
AIR CONDITIONER NOISY DURING OPERATION.
Step 1.
Check expansion valve. (See paragraph 5-30.)
Replace if defective.
Step 2.
Check compressor for internal noise and loose mounting. (See paragraph 5-32.)
a. Repair loose mounting.
b. Replace compressor if defective.
5-8
