TM 9-4120-399-14
5-10. LEAK TESTING THE REFRIGERANT SYSTEM. (Continued).
(c) Connect a nitrogen pressure regulator and nitrogen bottle to the
center hose connection of the charging manifold.
(d) Open the charging manifold valves,
(e) Open the nitrogen tank valve and pressurize the system to 350
psig (24.7 kg/cm2).
(f) Perform leak tests.
(g) If a leak is found, discharge and purge the system and repair
leak. See specific instructions for components to be removed.
(h) If a leak was not found and refrigerant 22 was used to
pressurize the system, see charging instructions. (See para.
(2) To pressurize a system that has been discharged and purged for leak testing with an
electronic detector:
(a) Remove the hose connection protective caps from the high and
low pressure service valves.
(b) Connect the hoses from a charging manifold to the service
valves.
CAUTION
Connect the refrigerant 22 cylinder so that only gas will be used for
(c) Connect a drum of refrigerant 22 to the center hose connection
of the charging manifold.
(d) Open the charging manifold valves.
(e) Open the refrigerant drum valve slightly and adjust as necessary
to prevent formation of frost, and allow system pressure to build
up until the gages read 40-50 psig (2.8 - 3.5 kg/cm2).
(f) Close the charging manifold valves and the refrigerant drum
valve.
(g) Remove the refrigerant 22 cylinder from the center hose
connection.
5-14
