Exact amount of Freon

Why do I need to use and exact amount of Freon?

Today's A/C systems use smaller amounts of Freon. No longer is it 2 to 4 lbs, but rather 18 to 38 oz. With tight compressor tolerances and lubricant mixed with the Freon, the mixture must be just right to enter the compressor as a mist. Wrong mixtures will either under lubricate or slug(too much oil and or Freon build up behind the expansion device orifice or in the compressor cylinder chamber) the compressor causing premature failures. You don't know how much liquid Freon is in a system so you should recover the old Freon, evacuate and add the correct charge. Always check the OEM oil and Freon spec at DiscountAutoAC-CompressorParts.com for the correct charge of Freon and oil.