Evacuating and Charging Notes

If the System has been opened for any repair or the refrigerant charge has been lost, the system must be evacuated prior to charging.

Evacuation and charging is a combined procedure, and all gage lines must be purged with R-12 prior to charging.

There are two evacuation and charge procedures.
1. J-23500-01 Charging Station Method.
2. Drum Method.

CAUTION: Under no circumstances should alcohol be used in the system in an attempt to remove moisture. Damage to the system components could occur.


VACUUM PUMP CHECK
Before connecting a vacuum pump to the A/C system, connect the pump to the low-pressure gage to determine the vacuum pump's capability.
If the vacuum pump is unable to reach at least 94.5 - 97.9 kPa (28"- 29" Hg.) vacuum, recheck the connections for leaks.
If no leaks are found, the vacuum pump may require repair.

When a vacuum pump is used for system evacuation, it must be able to reach (94.5 - 97.9 kPa, 28"- 29" Hg.) (or as adjusted for altitude).
This specification can be reached only at or near sea level. For each 304.8 m (1,000 feet) above sea level, lower the specification by 3.37 kPa (1" Hg.).
For example, at 1,524 m (5,000 ft.) elevation, only 77.67 - 84. 42 kPa (23"- 24" Hg) vacuum is required.