This work presents an experimental investigation on energy and exergy performance characteristics of a typical residential split air conditioning system. Analyses are performed for different atmospheric temperatures. On the basis of experimental data coefficient of performances (COP), exergy efficiencies (psi) and exergy destructions ((E)over dotx(dest)) of whole system and its each subunits are evaluated. The results also demonstrate that the atmospheric temperature (T-atm) rise affects the system performance as well as its performance of components substantially. The values of Exdest in the compressor and capillary tube increase with an increase of Tatm but the values of Exdest in the condenser and evaporator decrease with an increase of Tatm. When Tatm is risen from 20 degrees C to 46 degrees C; it is determined that power consumption comp (W) over bar (comp) and (E) over dotx(dest) of the air conditioning system are enhanced by 47.1% and 24.5%, respectively, but. is reduced by 38.8%.