Disclosed is a non-flammable refrigerant composition consisting of pentafluoroethane in an amount from 62-70% based on the weight of the composition selected from 1,1,1,2-tetrafluoroethane, 1,1,2,2-tetrafluoroethane, or a mixture thereof in an amount from 26 to 36% by weight based on the weight of the composition and mixture of dimethyether and n-butane in an amount of from 1-4% by weight based on the weight of the composition. Optionally, the composition may include at least one lubricant, at least one additive or combinations thereof.