REFRIGERATING MACHINE OIL AND REFRIGERATING MACHINE WORKING FLUID COMPOSITION

摘要

The present invention provides a refrigerating machine working fluid composition containing a refrigerating machine oil and a refrigerant including difluoromethane. The refrigerating machine oil contains: a first ester having a dynamic viscosity at 100°C of 7.0 mm2/s or greater, the first ester being a polyol ester of dipentaerythritol and at least one type of fatty acid selected from C4-10 fatty acids; and a second ester which is a complex ester of a C6-12 polybasic acid, a C4-18 monohydric alcohol or a C4-18 fatty acid, and a polyhydric alcohol including at least one species selected from neopentyl glycol, trimethylolpropane, and pentaerythritol.