TM 9-4120-404-14
Section III. DIRECT SUPPORT MAINTENANCE PROCEDURES
4-5. GENERAL.
a. The procedures in this section cover items which appear in the direct support maintenance level on the
Maintenance Allocation Chart (MAC) which is in Appendix B.
b. When working on the refrigeration system there are certain general maintenance procedures which may need to
be performed at some point during the specific repair or replacement of items within the refrigeration system. Paragraph
4-6 covers these general procedures.
c. The refrigeration system must be completely recovered before any maintenance is performed on system
components. Read and understand all instructions prior to attempting repairs. Leak testing and dehydrator replacement
are required after any system component has been removed and replaced. The system must be evacuated before it is
charged. The system must be properly charged to function properly.
WARNING
DANGEROUS CHEMICAL
(R22)
is used in this equipment.
DEATH
or severe injury may result if personnel fail to observe safety precautions. Use
great care to avoid contact with liquid refrigerant gas being recovered under
pressure. Sudden and irreversible tissue damage can result from freezing. Wear
thermal protective gloves and a face protector or goggles in any situation where
skin-eye-contact is possible. Prevent contact of refrigerant gas with flame or hot
surfaces. Heat causes refrigerant to break down and form carbonyl chloride
(phosgene), a highly poisonous and corrosive gas.
WARNING
REFRIGERANT UNDER PRESSURE
is used in the operation of this equipment.
DEATH
or severe injury may result if you fail to observe safety precautions. Never use a
heating torch on any part that contains refrigerant 22. Do not let liquid refrigerant
touch you, and do not inhale refrigerant gas.
4-4