Electronic Halogen Leak Detector
TOOLS REQUIREDJ 39400 Halogen Leak Detector
A halogen leak detector is the most useful tool for locating refrigerant leaks. The J 39400 is a small unit which operates on 12 V DC. The J 39400 provides an audible signal which increases in frequency as the unit detects R-134a. Follow the instructions included with the unit in order to properly calibrate the instrument. Use the detector in the proper setting for the type of tested refrigerant. Set the detector gas switch to R-134a prior to use.
The most common leaks occur at the refrigerant fittings or connections. The leaks may be the result of any of the following conditions:
^ Improper torque
^ Damaged O-rings
^ Lack of lubricant on the O-rings
^ Dirt or debris across the O-ring
^ Small pieces of lint from cotton gloves or shop cloths on the O-ring
In order to successfully use the J 39400 or any other electronic leak detector, maintain a proper scan rate. Carefully follow the manufacturer's instructions regarding calibration, operation, and maintenance. During testing, completely circle each joint using the probe at a rate of at 51 mm (1-2 in) per second. Place the tip of the probe less than 6 mm (0.25 in) away from the surface. Do not block the probe tip air intake. A leak exists when the audible tone changes from a steady 1-2 clicks per second to a continuous alarm. Frequently adjust the balance knob in order to maintain the rate of 1-2 clicks per second.
IMPORTANT: Halogen leak detectors are sensitive to the following items:
^ Windshield washing solutions
^ Many solvents and cleaners
^ Some adhesives used in the vehicle
Thoroughly clean the surfaces in order to prevent a false warning. Dry the surfaces carefully. Liquids will damage the detector.
Use this procedure in order to test the following components:
^ The evaporator inlet
^ The evaporator outlet The accumulator inlet
^ The accumulator outlet
^ The condenser inlet
^ The condenser outlet
^ All brazed joints
^ All welded joints
^ The compressor rear head
^ The housing joints
IMPORTANT: Follow a continuous path around the refrigerant system in order to ensure that you do not miss any possible leaks. In order to ensure that the entire system is free from leaks, test all of these areas, even after you have found one leak.
Test the following areas:
^ The in-line connections
^ The service ports
^ The pressure switch