In order to study the impact of the change of outlet water temperature on the heating performance of air-cooled heat pump chiller which adopts electronic expansion value and modularity energy adjustment system，the experiment is carried out on 5 this kind of unit with 60kW refrigerating output in the variable working conditions of outlet water temperature in the range of 39—50℃，ambient temperature in the range of -10～13℃ and relative humidity 90%.The heating capacity of the unit between 34.6—78.8kW，consumed power between 16.2—22.2kW，heating COPh between 1.77—4.20.The effects of outlet-water temperature of condenser on heating capacity，input power and COPh were examined，which provides the basis for energy saving operation and optimization design.