operating point of the compressor to the right lowering the compression ratio the suction pressure and mass flow rate can be raised until the compressor is operating near the stonewall point a first embodiment of the invention is illustrated in fig1 in each stage a fixed recycle pressure safety valve psv 102 202 302 which may be located at the discharge of the compressor 104 204 304 or downstream of the aftercooler 106 206 306 pipes compressed gas back to an optional suction drum 108 208 308 in fig1 a recycle psv is located downstream of the aftercooler in each stage and compressed refrigerant is transmitted to the optional suction drum each recycle psv has a lower set point than the relief psv 110 210 310 which is open during a blocked discharge event embodiments of the present invention may utilize one or more stages although it is illustrated in embodiments having three stages in fig1 and 2 also some of the elements in the embodiments shown in fig1 and 2 are optional including the aftercooler 106 206 306 the suction drum 108 208 308 the relief psv 102 202 302 in fig1 and the recycle pressure relief valves 122 222 322 in fig2 for example in one variation wherein there is.