Refrigerant compositions are disclosed which comprise: (a) pentafluoroethane, octafluoropropane, trifluoromethoxydifluoromethane or hexafluoro-cyclopropane, or a mixture of two or more thereof, in an amount from 5 to 60 % based on the weight of the composition, (b) pentafluoroethane, 1,1,1,2- or 1,1,2,2-tetrafluoroethane, 1,1-difluoroethane, trifluoromethoxypentafluoroethane, 1,1,1,2,3,3,3-heptafluoropropane or 1,1,1,2,2,3,3-heptafluoropropane, or a mixture of two or more thereof, in an amount from 30 to 94 % by weight based on the weight of the composition and (c) an unsubstituted hydrocarbon of the formula CnHm in which n is at least 4 and m is at least 2n-2, other than methyl propane, in an amount from 1 to 10 % by weight based on the weight of the composition.