Evacuating the System


Air conditioning refrigerant or lubricant vapor can irritate your eyes, nose, or throat. Be careful when connecting service equipment. Do not breathe refrigerant or vapor.

If accidental system discharge occurs, ventilate work area before resuming service.

Additional health and safety information may be obtained from the refrigerant and lubricant manufacturers.

  1. When an A/C System has been opened to the atmosphere, such as during installation or repair, it must be evacuated using a R-134a refrigerant recover/recycling/charging station (If the system has been open for several days, the receiver/dryer should be replaced, and the system should be evacuated for several hours.)
  3. Connect a R-134a refrigerant recovery/recycling/charging station (A) to the high-pressure service port (B) and the low-pressure service port (C), as shown, following the equipment manufacturer's instruction. Evacuate the system.

    Click image to see an enlarged view

    Fig. Air conditioning evacuation diagram

  5. If the low-pressure does not reach more than 93.3 kPa (27.6 in.Hg) in 15 minutes, there is probably a leak in the system. Partially charge the system (see page HA-24), and check for leaks.