PURGING THE REFRIGERANT SYSTEM.
is used in this equipment.
or severe injury may result if personnel fail to observe safety precautions.
Use great care to avoid contact with liquid refrigerant gas being discharged
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.
REFRIGERANT UNDER PRESSURE
is used in the operation of this equipment.
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.
a. Supplies. To purge the refrigerant system you will need the following items.
b. Preliminary procedure.
The refrigeration system must be purged with dry nitrogen cylinder,
(Appendix E, item 2), before
on any component.
A flow of dry nitrogen between 1 and 2 cfm (0.028-0.057 m3/minute)
should be continued during all brazing operations to minimize internal
oxidation and scaling.
Nitrogen is an inert gas. However, it also presents danger as a suffocant
and, therefore, must also be discharged in a ventilated location.
Nitrogen cylinders are pressurized containers. The pressure in the cylinder
can exceed 2000 psig. A nitrogen pressure regulator should be used at
all times when nitrogen is used for leak check or purge operations.