Patent ID: 6843930

Claim:
A refrigerant composition for use in high back pressure condition, containing a refrigerant and an additive, wherein a) the refrigerant is mixture of propane and propylene, the content of the propane is in an amount of 20˜45 wt %, the content of the propylene is in an amount of 55˜80 wt % and the sum of the propane and the propylene is 100 wt % based on the total weight of the refrigerant, b) the additive is selected from the group consisting carbon dioxide (CO 2 ), trifluoromethyl iodide (CF 3 I) and mixture thereof, the content of the additive is in an amount of less than 5 wt % based on the refrigerant, and c) the refrigerant composition shows an azeotropic behavior.