Electronic Leak Detection Method

TOOLS REQUIRED
J 39400-A Halogen Leak Detector

Use the J 39400-A when testing for refrigeration system leaks. This unit operates on a 12 volt DC and provides an audible signal which increases in frequency when a refrigerant leak is detected. Properly calibrate the tool to the instructions and use at the proper setting for the system being tested. The J 39400-A has the following three settings:
^ R-12
^ R-134a
^ Gross leaks - for isolating very large leaks already found at one of the other settings

The J 39400-A is sensitive to windshield washing solution, many solvents and cleaners, and some adhesives. Work on a clean and dry surface. The following connections may all be tested using this detector, each connection being completely circled moving at 20-50 mm (1-2 inches) per second with the tip of the probe no more than 6 mm (0.25 in) from the surface:




1. Test the refrigerant pressure sensor.




2. Test the service valves.




3. Test the entire length of the hoses or tubes.
4. Test the evaporator core hose or tube connections.
5. Test the compressor rear head.
6. Test the compressor hose assembly connections.
7. Test the accumulator connections.
8. A leak is indicated when the audible tone goes from a steady 1-2 clicks per second to a solid alarm. The balance knob should be adjusted frequently in order to maintain the 1-2 clicks per second.

If a leak is not found, proceed to the Refrigerant Leak Diagnosis table.