| abstract |
To provide a working fluid composition for a refrigerator and a refrigerator oil capable of achieving both wear resistance and stability. A base oil comprising an ester of a polyhydric alcohol and a fatty acid, a refrigerating machine oil containing an epoxy compound and a phosphorus compound, and a fluoropropene refrigerant, the polyhydric alcohol containing pentaerythritol and dipentaerythritol. The fatty acid contains at least one selected from fatty acids having 4 to 9 carbon atoms, and the epoxy compound and the phosphorus compound satisfy the condition represented by the following formula (1). [In formula (1), NE is the number of epoxy groups per molecule of the epoxy compound, ME is the molecular weight of the epoxy compound, WE is the content of the epoxy compound based on the total amount of refrigerating machine oil, and NP is the phosphorus per molecule of the phosphorus compound. The number of atoms, MP is the molecular weight of the phosphorus compound, and WP is the content of the phosphorus compound based on the total amount of the refrigerating machine oil. ] [Selection figure] None |