Leak Testing - Refrigerant System

Test for leaks whenever a refrigerant leak is suspected and when performing a service operation which disturbs lines or connections.


ACCESS FITTING CAPS
All GM high side and low side access fittings are supplied with a black plastic cap and seal assembly which provide the primary refrigerant seal for the service fittings.

If the cap and seal assembly is missing or loose, a significant amount of refrigerant may leak through the valve core, located in the access fining, which can result in loss of A/C system cooling.

When servicing the vehicle's A/C system, make sure all access fining cap seals are in place and tight. Cap seals should be threaded until contact with O-ring seal is made and then tightened 1/4-1/2 additional turn to insure a proper seal.


LIQUID LEAK DETECTORS
There are a number of locations (fittings, valves, etc.) on the air conditioning system where a liquid leak detector solution may be used to pinpoint refrigerant leaks.

When the test solution is applied to the suspected area (using the swab attached to the bottle cap) bubbles will form within seconds if there is a leak.

For areas with restricted access (such as Sections of the evaporator and condenser) an electronic leak detector is more practical for determining and locating leaks.

ELECTRONIC LEAK DETECTORS
Electronic leak testers can accurately determine leaks in areas that are difficult to test due to poor visibility or inaccessibility.

The H-10 Leak Detector J 26934 is a 110 volt, A/C powered tester while the Autobalance Refrigerant Leak Detector J 38505 is a portable, battery operated model. Both models provide visual and/or audible signals to indicate leak detection.

The successful use of electronic leak detectors depends upon carefully following the manufacturers instructions regarding calibration, operation and maintenance. Battery condition is especially important to the accuracy of the portable battery powered model J 38505 and is monitored by a low battery indicator.