| 摘要 |
A two-step process comprising as a first step draining a refrigerant heat transfer fluid made of molecules containing at least one chlorine atom per molecule and mineral oil lubricant dissolved therein from an unflushable compressor and associated piping in a vehicle air conditioner, thereby leaving a mineral oil residue. The second step comprises replacing the refrigerant heat transfer fluid in all parts of the vehicle air conditioner designed to contain such fluid with a replacement heat transfer fluid. The replacement fluid consists essentially of 1,1,1,2-tetrafluorethane and a composition of matter suitable for serving as the lubricant or lubricant base stock. The composition of matter is capable of forming a soluble clear solution with a mineral oil residue in a weight ratio of mineral oil to composition of at least 25:100 and forming a single phase with 1,1,1,2-tetrafluoroethane between -55° C. and +71° C. The composition of matter is a liquid having a viscosity between 45 and 220 centistokes at 40° C. and consisting essentially of a mixture of polyol esters derived primarily from pentaerythritol and an acid mixture comprising isopentanoic acid, branched acids of eight and/or nine carbon atoms and adipic acid.
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