As the pump continues operating, the dry air will mix with and dilute any remaining moisture. Secure the opening which feeds the dry air to the system. At this time, the dehydration process is complete. Close the valves and disconnect the vacuum pump. Sometimes it is impossible to obtain a temperature as low as 35 F in the vacuum indicator.
Excess moisture is present in the system.
Because of the acid being formed, the dehydration procedure should be conducted for longer periods. Absorbed refrigerant is present in the lubricating oil contained in the compressor crankcase. Remove the lubricating oil from the crankcase before proceeding with the dehydration process. Air is leaking into the system. The leak must be found and stopped.