Working fluid, freezer, and freezer oil

A refrigerating machine comprising a refrigerant circulation system comprising a compressor, a condenser, an expansion mechanism, an evaporator, and an accumulator,

• wherein the refrigerant circulation system is filled with a working fluid comprising a refrigerant and a refrigerating machine oil,
• the refrigerant consists of a hydrocarbon refrigerant having 2 to 4 carbon atoms,
• the refrigerating machine oil has a mixed aniline point of 20° C. or higher and 50° C. or lower and a viscosity index of 140 or more,
• an amount of the refrigerant dissolved in the working fluid is 40% by mass or less under conditions of a temperature of 80° C. and an absolute pressure of 2.8 MPa,
• the refrigerating machine oil has a kinematic viscosity at −10° C. of 200 mm2/s or more and 3000 mm2/s or less, and
• refrigerating machine oil has a flash point of 250° C. or higher.

A refrigerating machine oil filled in a refrigerant circulation system comprising a compressor, a condenser, an expansion mechanism, an evaporator, and an accumulator, with a refrigerant,

• wherein the refrigerant comprises a hydrocarbon refrigerant having 2 to 4 carbon atoms,
• the refrigerating machine oil has a mixed aniline point of 20° C. or higher and 50° C. or lower and a viscosity index of 140 or more,
• an amount of the refrigerant dissolved in the working fluid is 40% by mass or less under conditions of a temperature of 80° C. and an absolute pressure of 2.8 MPa,
• the refrigerating machine oil has a kinematic viscosity at −10° C. of 200 mm2/s or more and 3000 mm2/s or less,
• the refrigerating machine oil comprises no mineral oil, and
• refrigerating machine oil has a flash point of 250° C. or higher.