Groundwater source heat pump system: The groundwater system generally adopts an open loop system, that is, a certain number of pumping wells and recharge wells. The cooling water is radiated to the deep underground well through the heat exchanger (heat absorption in winter), and the groundwater is pumped from the water intake well into the heat exchanger for heat absorption (heat dissipation in winter) and then returned to the underground by the returning water well. The groundwater system is suitable for areas with abundant groundwater resources. The temperature of groundwater is stable all the year round and is not affected by outside air temperature. Therefore, the heat pump unit can operate efficiently.