* Environmental protection: using lake water as the cooling and heating source, energy conversion, reducing CO2 and other atmospheric pollutant emissions, avoiding cooling tower noise and mould pollution;
* Energy saving: cooling and heating source temperature conditions are better than ambient air, high operating efficiency;
* Cost saving: integrating heating, air conditioning and domestic hot water, enhancing economy;
* Stable: water temperature conditions The fluctuation range is much smaller than that of the air temperature, which makes the operation reliable and stable.
* Flexible: the unit is optional in various forms, and the decentralised water fan can be used for air conditioning, heating and four controls at the same time.
* Aesthetic: compared with air-cooled heat pumps, there is no need for an outdoor unit, which ensures the aesthetics of the building facade.

Design Standard for Energy Efficiency of Public Buildings Design Standard for Energy Efficiency of Public Buildings" GB50189-2005, p. 18, "Air conditioning and heating sources of heat and cold", Article 5; When natural water resources or geothermal heat are available, water (ground) source heat pumps are suitable for cooling and heating.

Areas with abundant surface water bodies.

Open cycle, water treatment required.
Summer: heat pump unit transfers indoor heat to river/river/lake water.
Winter: heat pump unit draws heat from river/river/lake water to heat the room.