A non-flammable refrigerant composition for a HVACR system that includes R134a refrigerant, a hydrofluorocarbon refrigerant that has a global warming potential (GWP) of less than 150 or a hydrofluoroolefin refrigerant, and CF3I. A method of making a refrigerant composition for a HVACR system that includes selecting an amount of a first refrigerant that is a hydrofluorocarbon refrigerant or a hydrofluoroolefin refrigerant, selecting an amount of CF3I, and selecting an amount of R134a refrigerant. A method of retrofitting a refrigerant composition in an HVACR system that includes adding one or more compounds to the refrigerant composition. The retrofitted composition including R134a refrigerant, a hydrofluorocarbon refrigerant having a GWP of less than 150, and CF3I, or R134a refrigerant, a hydrofluoroolefin refrigerant, and CF3I.