A refrigeration cycle apparatus including a refrigeration circuit, the refrigeration circuit including a compressor, an outdoor heat exchanger, an indoor heat exchanger, and an expansion valve, wherein a refrigerant is sealed within the refrigeration circuit, the refrigerant contains trifluoroiodomethane, the compressor is filled with a refrigerator oil, and the refrigerator oil contains at least one of a first compound represented by the following chemical formula 1 and a second compound represented by the following chemical formula 2: ##STR00001##

An object of the present invention is to provide a lubricant which has excellent lubrication performance and is able to exhibit excellent lubrication performance even when under extreme pressure conditions. The present invention relates to a complex polyester composition containing polyester obtained by condensing polyhydric alcohol having at least two hydroxyl groups, a dicarboxylic acid having 44 carbon atoms, and monohydric alcohol. Further, the present invention relates to a lubricant composition containing the complex polyester composition, and a lubricant and a production method for a complex polyester composition.