abstract |
A composition for a heat cycle system which has excellent lubrication properties and which contains a heat cycle working medium usable as a substitute for R410A and having a low global warming potential, and a heat cycle system using said composition are provided. This composition for a heat cycle system contains a heat cycle working medium that contains an unsaturated fluorinated hydrocarbon compound of a specific structure, and a refrigerator oil which has an insulation breakdown voltage of 25kV or greater, a hydroxyl value of 0.1mgKOH/g or less, and an aniline point between -100°C and 0°C; this heat cycle system uses this composition for a heat cycle system. |