Whenever a refrigerant leak is suspected in the system or a service operation performed which results in disturbing lines or connections, it is advisable to test for leaks.

Caution: Refer to Vehicle Lifting Caution in the Preface section.

Important: Rinse soap solution from fitting before making repair.

There are a number of locations, such as fittings, valves, etc. on air conditioning system where a liquid leak detector solution may be used to pinpoint refrigerant leaks. Apply soap solution to the area in question. Bubbles will form indicating a leak.

For restricted access areas, such as sections of evaporator and condenser, an electronic leak detector is advisable.

Caution: Care should be taken to prevent personal injury which could occur due to touching a hot engine when testing. Tests should be done with the engine off and as cool as possible. Do not operate the detector in a combustible atmosphere since its sensor operates at a high temperature.

The successful use of this and any other electronic leak detector depends greatly upon the scan rate and upon carefully following manufacturer's instructions regarding calibration, operation, and maintenance. Each joint must be completely circled moving at 25-50 mm (1-2 in) inches per second with tip of probe as close to surface as possible but no more than a 6.35 mm (1/4 in) away and without blocking air intake. A leak is indicated when the audible tone goes from a steady one to two clicks per second to a solid alarm. The balance knob should be adjusted frequently to maintain the 1-2 clicks per second rate.