In accordance with the present invention refrigerant compositions are disclosed. The compositions comprise HFC-32, HFC-125, HFO-1234yf, HFC-134a, and CO2. The refrigerant compositions are useful in processes to produce cooling and heating, in methods for replacing refrigerant R-410A or R-22, and in refrigeration, air conditioning or heat pump systems. These inventive compositions are non-flammable and match cooling performance for R-22 and R-410A within ±15%. Additionally, these compositions may serve as replacements for R-404A, R-507, R407A, R407C and/or R-407F in refrigeration, air conditioning or heat pump systems. The compositions as described herein have unexpected flammability properties.