Electronic Halogen Leak Detector
TOOLS REQUIREDJ 39400-A Halogen Leak Detector
IMPORTANT: Halogen leak detectors are sensitive to the following items:
^ Windshield washing solutions
^ Many solvents and cleaners
^ Some adhesives used in the vehicle
Ensure that the surfaces are clean in order to prevent a false warning. Ensure that the surfaces are dry, as 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 in order to find any possible leaks. Test all areas of the system for leaks.
This type of leak detector is the most useful tool in order to locate refrigerant leaks. The J 39400-A is a small unit that operates on 12 volts DC. The J39400-A provides an audible signal that 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-ring
^ Lack of lubricant on O-rings
^ Dirt or debris across the O-ring
In order to successfully use the J 39400-A or any other electronic leak detector, maintain a proper scan rate. Carefully follow the manufacturer's instructions regarding the following items:
^ Calibration
^ Operation
^ 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 within 6 mm (0.25) of 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.
Use these guidelines when testing the following components for leaks:
^ The refrigerant lines
^ The pressure sensor
^ The service valve