TM 9-4120-407-14
4-16. LEAK TESTING THE REFRIGERANT SYSTEM.
This task covers:
Testing
Tools
Equipment Conditions:
Refrigeration Unit Service Tool Kit
Materials/Parts
Never pressurize refrigerant lines with oxygen, mixture with oil
could cause an explosion.
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.
NOTES
Either a refrigerant gas leak detector or a strong solution of liquid
detergent in water can be used to test for leaks.
If an electronic refrigerant gas leak detector is available, it
should be used in accordance with the procedures contained in
TM 9-4940-435-14, "Leak Detector, Refrigerant Gas".
To perform leak testing by use of the electronic detector, it is
necessary that the system be pressurized with a proportion of
refrigerant gas.
Testing.
(1) To pressurize a system that has some refrigerant charge:
( a ) Connect the charge hose to a Refrigerant R-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.
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