The development status of a compact large displacement non-fluorocarbon high efficiency compressor is reported. The compressor developed is a positive displacement, rotary constrained vane machine. Compressor performance results using two different refrigerants are reported. One refrigerant was a hydrocarbon whereas the other was a fluorocarbon. Data was obtained using a water calorimeter test stand. Test results demonstrated COP's in the range of 3.5 to 4.5 with both the non-fluorocarbon and fluorocarbon refrigerants at air conditioning test conditions. Maximum overall compressor efficiencies of slightly over 80% were obtained.