Refrigerant Vacuum Procedures

NOTE:

It is have to vacuum procedures, before the charging. This vacuum procedures is done to remove all air and moisture from the unit after each part has been fitted, the system shall vacuum procedures for more than 10 minutes.

When an A/C System has been opened to the atmosphere, such as during installation or repair, it must be evacuated using an R-1234yf refrigerant Recovery/Recycling/Charging System. (If the system has been open for several days, the receiver/dryer should be replaced, and the system should be evacuated for several hours.)

Courtesy of HYUNDAI MOTOR AMERICA
if the gauge remains in the vacuum area with the high and low pressure valves closed after 10 minutes, vacuum is preformed normally. If the pressure is increase, conduct a leak test.
1. Refrigerant charging
2. Using a leak detector, conduct a leak test. If a refrigerant leak is detected and repair.
3. Drain the refrigerant again and vacuum procedures the system.
Close the high pressure valve and low pressure valve after vacuum procedures more than 10 minute.