| 摘要 |
Provided are a working medium for a heat cycle, which can be a replacement for R410A, has a low global warming coefficient and exhibits high durability; a composition for a heat cycle system, which contains this working medium; and a heat cycle system that uses this composition. The working medium for a heat cycle contains trifluoroethylene, 2,3,3,3-tetrafluoropropene and difluoromethane, wherein the ratio of the total quantity of trifluoroethylene, 2,3,3,3-tetrafluoropropene and difluoromethane relative to the overall quantity of the working medium is greater than 90 mass % but not greater than 100 mass %, the ratio of the quantity of trifluoroethylene relative to the total quantity of trifluoroethylene, 2,3,3,3-tetrafluoropropene and difluoromethane is not less than 10 mass % but less than 70 mass %, the ratio of the quantity of 2,3,3,3-tetrafluoropropene relative to the total quantity of trifluoroethylene, 2,3,3,3-tetrafluoropropene and difluoromethane is not greater than 50 mass %, and the ratio of the quantity of difluoromethane relative to the total quantity of trifluoroethylene, 2,3,3,3-tetrafluoropropene and difluoromethane is greater than 30 mass % but not greater than 75 mass %. |
