TM 9-4120-402-14
5-14. FLUSHING THE REFRIGERANT SYSTEM. - continued
WARNING
Burns can result from contact with acid formed by burn out of oil and refrigerant. Avoid inhaling
fumes and wear a gas mask if area is not thoroughly ventilated. Wear protective goggles or
glasses to protect eyes. Wear gloves to protect hands.
(e)
Fill reservoir with refrigerant R-114 and start pump. Keep reservoir full until refrigerant begins to pour out of
the return line. Continue flushing for at least 15 minutes.
(f)
Reverse the unit discharge and suction line connections, replace the filter with a new filtering medium, and
flush the system for at least 15 minutes.
b.
Purge.
WARNING
The pressure in a nitrogen cylinder can exceed 2000 psi. A nitrogen pressure regulator should
be used at all times to avoid personal injury.
Nitrogen is an inert gas that can cause suffocation and must be discharged in a well ventilated
area.
Purge the system with nitrogen at approximately 30 psig (2.11 kg/cm2) as follows:
(a)
Remove the pump, reservoir, filter, and refrigerant desiccant dehydrator jumper. Place an empty container
below the compressor connections, and connect the cylinder of dry nitrogen to each filter-drier connection in
turn. Blow down each leg of the system for at least 30 seconds after moisture stops being discharged.
(b)
Disconnect the dry nitrogen cylinder. Cap or plug open connections if compressor and filter-drier are not to be
installed immediately.
NOTE
FOLLOW-ON MAINTENANCE:
5-42