... : *CE *domestic air conditioning *residential heat pump water source heat pump/heat pump/water to water heat pump1.CE,CCC,ISO approval2.Easy ... exchangers, save 65 to 80%, operating costs comparedwith other conventional water heating equipment (oil-fired boiler, gasboiler, electric boilers, and etc.)Quiet ... will not cause environmental pollutionwater source heat pump/heat pump/water to water heat pump