Refrigerant System Leaks

REFRIGERANT SYSTEM LEAKS

WARNING: R-134a service equipment or vehicle A/C system should not be pressure tested or leak tested with compressed air. Mixture of air and R-134a can be combustible at elevated pressures. These mixtures are potentially dangerous and may result in fire or explosion causing property damage, personal injury or death.
Avoid breathing A/C refrigerant and lubricant vapor or mist. Exposure may irritate eyes, nose and throat. Use only approved service equipment meeting SAE requirements to discharge R-134a system. If accidental system discharge occurs, ventilate work area before resuming service.


Connect a suitable manifold gauge set and determine if the static A/C system pressure is above or below 345 kPa (50 psi) Refrigerant System Service Equipment. If less than 345 kPa (50 psi), proceed to SYSTEM EMPTY. If greater than 345 kPa (50 psi), go to SYSTEM LOW.

SYSTEM EMPTY

1. Evacuate the refrigerant system to the lowest degree of vacuum possible (approximately 28 in Hg.) Refrigerant System Evacuate. Determine if the system holds a vacuum for 15 minutes. If vacuum is held, a leak is probably not present. If system will not maintain vacuum level, proceed to STEP 2.
2. Prepare and dispense 0.284 kilograms (10 ounces) of R-134a refrigerant into the evacuated refrigerant system Refrigerant System Charge and proceed to STEP 1 of the System Low procedure.
SYSTEM LOW

3. Position the vehicle in a wind free work area. This will aid in detecting small leaks.
4. Operate the heating-A/C system with the engine at idle under the following conditions for at least five minutes.
- Doors or windows open
- Transmission in Park
- A/C-heater controls set to outside air, full cool, panel mode, high blower and with A/C compressor engaged
- If equipped with rear heating-A/C system, set rear controls to full cool and high blower

CAUTION: A leak detector only designed for R-12 refrigerant will not detect leaks in an R-134a refrigerant system.

5. Shut the vehicle Off and wait 2-7 minutes. Then use an electronic leak detector that is designed to detect R-134a refrigerant and search for leaks. Fittings, lines or components that appear to be oily usually indicate a refrigerant leak. To inspect the A/C evaporator for leaks, insert the leak detector probe into the drain tube opening or an air outlet. A dye for R-134a is available to aid in leak detection. Use only DaimlerChrysler approved refrigerant dye.