NOVELTY - A composition contains Z-1,2-difluoroethylene and greater than or equal to 1 compound selected from 2,3,3,3-tetrafluoropropene, Z-1,2,3,3,3-pentafluoropropene, E-1,2,3,3,3-pentafluoropropene, 3,3,3-trifluoropropene, difluoromethane, pentafluoroethane, 1,1,2,2 -tetrafluoroethane, 1,1,1,2-tetrafluoroethane, 1,1,1-trifluoroethane, 1,1-difluoroethane, fluoroethane, 1,1,1,2,3,3,3-heptafluoropropane, 1,1,1,2,3,3-hexafluoropropane, 1,1,1,3,3,3-hexafluoropropane, 1,1,1,3,3-pentafluoropropane, propane, n-butane, isobutane, propylene, cyclopropane, n-pentane, isopentane, dimethylether, and trifluoroiodomethane.    USE - A composition for refrigerant composition, foam blowing agent, or sprayable composition used for refrigeration, air conditioning, heat pump, or power cycle system apparatus (all claimed).    ADVANTAGE - The composition provides unique characteristics to meet the demands of low or zero ozone depletion potential and lower global warming potential as compared to current refrigerants.    DETAILED DESCRIPTION - A composition comprises Z-1,2-difluoroethylene and greater than or equal to 1 compound selected from 2,3,3,3-tetrafluoropropene, Z-1,2,3,3,3-pentafluoropropene, E-1,2,3,3,3-pentafluoropropene, 3,3,3-trifluoropropene, difluoromethane, pentafluoroethane, 1,1,2,2 -tetrafluoroethane, 1,1,1,2-tetrafluoroethane, 1,1,1-trifluoroethane, 1,1-difluoroethane, fluoroethane, 1,1,1,2,3,3,3-heptafluoropropane, 1,1,1,2,3,3-hexafluoropropane, 1,1,1,3,3,3-hexafluoropropane, 1,1,1,3,3-pentafluoropropane, propane, n-butane, isobutane, propylene, cyclopropane, n-pentane, isopentane, dimethylether, trifluoroiodomethane, and bis(trifluoromethyl)sulfide (CF3SCF3). INDEPENDENT CLAIMS are included for:    (1) method of replacing refrigerant selected from R134a (1,1,1,2-tetrafluoroethane), R22 (chlorodifluoromethane), R12 (dichlorodifluoromethane), R404A (blend of pentafluoroethane, 1,1,1-trifluoroethane, and 1,1,1,2-tetrafluoroethane), R410A (blend of pentafluoroethane and difluoromethane), R407C ( blend of 1,1,1,2-tetrafluoroethane, pentafluoroethane, and difluoromethane), R413A (blend of octafluoropropane, 1,1,1,2-tetrafluoroethane, and isobutane), R417A (blend of pentafluoroethane, 1,1,1,2-tetrafluoroethane, and n-butane), R422A (blend of pentafluoroethane, 1,1,1,2-tetrafluoroethane, and isobutane), R422B (blend of pentafluoroethane, 1,1,1,2-tetrafluoroethane, and isobutane), R422C (blend of pentafluoroethane, 1,1,1,2-tetrafluoroethane, and isobutane), R422D (blend of pentafluoroethane, 1,1,1,2-tetrafluoroethane, and isobutane), R423A (blend of 1,1,1,2-tetrafluoroethane and 1,1,1,2,3,3,3-heptafluoropropane), R424A (blend of pentafluoroethane, 1,1,1,2-tetrafluoroethane, isobutane, n-butane, and isopentane), R426A (blend of pentafluoroethane, 1,1,1,2-tetrafluoroethane, n-butane, and isopentane), R428A (blend of pentafluoroethane, 1,1,1,2-tetrafluoroethane, propane, and isobutane), R430A (blend of difluoroethane-1,1 and isobutane), R434A (blend of pentafluoroethane, 1,1,1,2-tetrafluoroethane, 1,1,1-trifluoroethane, and isobutane), R437A (blend of pentafluoroethane, 1,1,1,2-tetrafluoroethane, n-butane, and n-pentane), R438A (blend of difluoromethane, pentafluoroethane, 1,1,1,2-tetrafluoroethane, n-butane, and isopentane), R507A (blend of pentafluoroethane and 1,1,1-trifluoroethane), and R502 (blend of chloropentafluoroethane and chiorodifluoromethane) in system that uses, is used, or is designed to use refrigerant which involves adding to system composition comprising Z-1,2-difluoroethylene and optionally, 2,3,3,3-tetrafluoropropene, Z-1,2,3,3,3-pentafluoropropene, E-1,2,3,3,3-pentafluoropropene, E-1,3,3,3-tetrafluoropropene, 3,3,3-trifluoropropene, difluoromethane, pentafluoroethane, 1,1,2,2-tetrafluoroethane, 1,1,1,2-tetrafluoroethane, 1,1,1-trifluoroethane, 1,1-difluoroethane, fluoroethane, 1,1,1,2,3,3,3-heptafluoropropane, 1,1,1,2,3,3-hexafluoropropane, 1,1,1,3,3,3-hexafluoropropane, 1,1,1,3,3-pentafluoropropane, propane, n-butane, isobutane, propylene, cyclopropane, n-pentane, isopentane, dimethylether, trifluoroiodomethane, and CF3SCF3;    (2) method of refrigeration, air-conditioning, or heating which involves evaporating and condensing composition functioning as refrigerant;    (3) method of forming foam which involves adding composition to foamable composition and reacting the foamable composition under conditions effective to form a foam;    (4) process of producing aerosol products which involves adding composition to active ingredients in aerosol container in which composition functions as propellant; and    (5) process for recovering heat which involves evaporating liquid phase working fluid comprising composition in heat exchanger in contact with system that produces heat, therefore producing vapor phase working fluid and passing vapor phase working fluid to expander in which mechanical energy is produced.