This paper presents the results of an experimental study to determine the effect of vapor-liquid refrigerant separation in a microchannel condenser of a MAC system. R134a is used as the working fluid. A condenser with a separation and a baseline condenser identical on the air side have been tested to evaluate the difference in the performance due to separation. Two categories of experiments have been conducted: the heat exchanger-level test and the system-level test. In the heat exchanger-level test it is found that the separation condenser condenses up to 7.4% more mass flow than the baseline at the same inlet and outlet temperature (enthalpy); the separation condenser condenses the same mass flow to the lower temperature than the baseline condenser does. In the system-level test, COP is compared under the same superheat, subcooling and refrigerating capacity. Separation condenser shows from 1.3% to 6.6% a higher COP than the baseline condenser.