In this paper, an innovative structure for an new evaporative condenser refrigerant pump air conditioning unit is proposed. This structure features a combination of air cooling and evaporative condensing systems on the condenser side of the unit and simultaneously utilizes circulating water to precool the air. The performance indices of the unit, such as the cooling capacity and energy efficiency ratio, are tested in an enthalpy difference laboratory in dry mode, wet mode and supplementary cooling mode. In addition, the influences of different factors of the unit are tested and analyzed via orthogonal experiments. The experimental results reveal that the annual energy efficiency ratio of the unit in Shenzhen can reach 9.27. In the orthogonal wet mode experiment, when the cooling capacity is taken as the evaluation index, the refrigerant pump has the greatest influence, and the optimal frequency is 60 Hz. Moreover, when the EER is taken as the evaluation index, the outdoor fan has the greatest influence, and the optimal air volume is 8000 m3/h. When the indoor fan has the greatest influence, the optimal air volume is 7000 m3/h. The experimental results show that the unit with air precooling and a composite condenser performs well and has a high energy–efficiency ratio, thereby serving as a new reference system for the design and operation control of an new evaporative condenser refrigerant pump air conditioning unit.