TM 9-4120-402-14
5-15. LEAK TESTING THE REFRIGERANT SYSTEM. - continued
Test.
(1)
To pressurize a system that has some refrigerant charge:
(a)
Connect the charge hose to a Refrigerant-22 cylinder.
(b)
Open the service manifold compound gauge, pressure gauge, and charge valves.
(c)
Check that service manifold vacuum valve is closed.
(d)
Open refrigerant cylinder valve and pressurize system to 100 psi (7.1 kg/cm2).
(e)
Test for leaks at all points of possible leakage using an electronic refrigerant gas leak detector.
(f)
If a leak is found, discharge and purge system, and repair leak. Retest for leaks. (See paragraph 5-12.)
(g)
If a leak was not found, check unit charge. (See paragraph 5-17.)
(2)
To pressurize a system that has been discharged and purged:
(a)
Connect the charge hose to a cylinder of Refrigerant-22 set to deliver gas only.
(b)
Open the service manifold compound gauge, pressure gauge, and charge valves.
(c)
Check that service manifold vacuum valve is closed.
(d)
Open refrigerant cylinder valve and pressurize system to 40-50 psi (2.8 - 3.5 kg/cm2).
(e)
Close service manifold valves and refrigerant cylinder valve.
(f)
Disconnect charge hose from the refrigerant cylinder.
(g)
Connect the charge hose to a nitrogen regulator and dry nitrogen cylinder.
(h)
Open the service manifold compound gauge, pressure gauge, and charge valves.
(i)
Open nitrogen cylinder valve and pressurize system to 350 psi (24.7 kg/cm2).
(j)
Close service manifold valves and nitrogen cylinder valve.
(k)
Test for leaks at all points of possible leakage using an electronic refrigerant gas leak detector.
(l)
If a leak is found, discharge and purge system, and repair leak. Retest for leaks. (See paragraph 5-12.)
(m) After performing leak tests, discharge and purge system before performing maintenance, or evacuating and
charging system, as appropriate. (See paragraphs 5-11 and 5-12.)
NOTE
FOLLOW-ON MAINTENANCE:
Remove service manifold (para 5-10).
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