Heat transfer compositions, methods and systems

A method of cooling in a heat transfer system comprising an evaporator, a condenser and a compressor, the process comprising:

• i) condensing a refrigerant comprising:
• at least about 97% by weight of a combination of the following three compounds, said combination consisting essentially of:
• about 49% by weight difluoromethane (HFC-32), about 11.5% by weight pentafluoroethane (HFC-125), and
• about 39.5% by weight trifluoroiodomethane (CF3I), wherein the percentages are based on the total weight of said three compounds;
• ii) evaporating said refrigerant in the vicinity of body or article to be cooled, wherein the evaporating temperature of said refrigerant is in the range of from about −40° C. to about −10° C.