TIF ZX Heated Pentode Refrigerant Detector - Manual (Page 13)

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4 . In windy areas, even a large leak can be difficult to find . Under these conditions, it is
best to shield the potential leak area from wind or breezes .
5 . A leak is a constant source of refrigerant, and when a true leak source is located, it
should produce a repeatable alarm each time it is approached . Intermittent (non-
repeatable) alarms are often caused by accumulations of refrigerant near or around
leak points .
6 . If an alarm occurs, and cannot be repeated when the probe tip is placed at the
same point again, it is unlikely there is a significant leak present at that point .
However, this may be indicative of a leak nearby – and can be used as a diagnostic
aid in leak finding .
sae J1628 Recommended Procedure
NOTE: Leak test automotive A/C systems with the engine turned OFF.
1 . The air conditioning or refrigeration system should be charged with sufficient
refrigerant to have gauge pressure of at least 340 kPa (50 psi) when not in
operation . At temperature below 15°C (59°F), leaks may not be measurable, since
this pressure may not be reached .
2 . Do not contaminate the detector probe tip nor part being tested . If the part is
particularly dirty, or condensation (moisture) is present, clean it with a dry shop
towel or shop air . Do not use cleaners or solvents, since the detector may be
sensitive to their ingredients .
3 . Visually trace the entire refrigerant system, and look for signs of air conditioning
lubricant leakage, damage, and corrosion on all lines, hoses, and components .
Check each questionable area with the detector probe, as well as fittings, hose-to-
line couplings, refrigerant controls, service ports with caps in place, brazed or
welded areas, areas around attachment points, and hold-downs on lines and
components .
4 . Follow the refrigerant system around in a continuous path so no areas of potential
leaks are missed . If a leak is found, continue to test the remainder of the system .
5 . At each area checked, move the probe around the location at a rate no more than
25 to 50 mm/second (1–2 inch/second), and no more than 5 mm (1/4 in .) from the
surface, and completely around the position . Slower and closer movement of the
probe greatly improves the likelihood of finding a leak (see Fig . 6) . Any increase in
the alarm rate is indicative of a leak .
Fig . 6