Patent ID: 8758641

Claim:
A method of producing refrigeration, said method comprising evaporating a composition in the vicinity of a body to be cooled and thereafter condensing said composition; wherein said composition consists of: a. a refrigerant or heat transfer fluid consisting of 2,3,3,3-tetrafluoro-1-propene (CH 2 ═CFCF 3 ) or 1,3,3,3-tetrafluoro-1-propene (CHF═CHCF 3 ); and b. at least one perfluoropolyether; and optionally c. a lubricant oil which is mineral oil or synthetic oil selected from the group consisting of alkylbenzene, polyol ester, polyalkylene glycols, polyvinyl ethers, carbonates, polyalphaolefin and combinations thereof; wherein said perfluoropolyether has two end groups; wherein each of the two end groups of the perfluoropolyether, independently, is either an unfunctionalized, branched or straight chain perfluoroalkyl radical, or a functionalized group selected from the group consisting of esters, hydroxyls, amines, amides, cyanos, carboxylic acids and sulfonic acids; and wherein said evaporating and said condensing is in a mobile air-conditioning system.