4, the design conditions: the cooling conditions: evaporator 1,2 water system in parallel, the fluorine system is independent, the inlet and outlet temperature 12/7 ℃, evaporation temperature 2 ℃; condenser 1,2 water system in parallel, fluorine system independent, Its inlet and outlet temperature 16/26 ℃, condensing temperature 31 ℃. Evaporator 1, 2 water system in series, independent fluorine system, evaporator inlet and outlet water temperature 15 / 9.5 ℃, evaporation temperature 5.5 ℃; evaporator 2 inlet and outlet temperature 9.5 / 5 ℃, evaporation temperature 1 ℃; condenser 1, 2 water system in parallel, fluorine system independent, the inlet and outlet temperature 40/45 ℃, condensation temperature 50 ℃. 5, the calculation results are as follows: ①cooling conditions: total system cooling capacity: Q0 = 466kW, the total system power: Pi = 89.5kW system cooling factor: Cop = 5.2 wells Water (water system parallel) Water withdrawal: 47.2m3 ② Heat pump conditions: Total system heat: Qk = 511kW, Total system power: Pi = 121.7kW System heating coefficient: Cop = 4.2 Well water (water system in series) : 34m3 After a winter and summer operation results show that the two wells in the local water conditions can be safe and reliable operation of the unit, cooling and heating effects to fully meet the requirements of users. Reduce the initial investment and operating costs, received a very good economic efficiency V. Conclusion: The use of this structure so that the evaporator inlet and outlet water both in the cooling of the 5 ℃ temperature difference, or in the heating 10 ℃ temperature difference, evaporation The heat exchanger performance is basically the same, that is, the evaporator heat transfer area in winter and summer under two conditions has been fully utilized. At the same time, heat pump operating conditions, the water decreased by 20%, the system's heating capacity increased by about 10%, Cop increased by about 7%. In summary, by improving the structure of the heat pump unit, changing the series and parallel of the evaporator water system, not only to achieve the saving of groundwater intake, reduce the number of wells and recharge wells, and rational use of the evaporator heat transfer Area, while increasing the system of heating and energy efficiency ratio. This will not only reduce the initial investment, but also reduce operating costs, with significant economic and social benefits, the application of water source heat pump in our country and development will play a catalytic role.