Harry in Ky
Veteran Member
It seems to me that the process of evacuating a system prior to charging will not only remove the air and moisture, but must also remove oil from the compressor as well. The oil level in my vacuum pump always rises when I pump out a system after installing a new compressor with a measured charge of oil installed. If this is the case, then what's the point of the careful measuring/pouring of oil into a compressor, evacuating, and then measuring more oil to be installed with/ahead of the refrigerant? Many new or reman compressors come with oil installed and often with a tag stating the specific quantity installed. It somehow seems pointless since no compressor can be installed and charged without first being evacuated.