Main function characteristic: Basing on the heat pump and air-condition working principle, making use of heat source from the air, exchanging heat by the air-condition system and transmitting heat to the water through the heating system and cold air into the indoors through the refrigerating system; Independent function of air-condition when no needing hot water, realizing combi-function of water heater & air condition, independent function of water heater & independent function of air condition, all-in-one; 3 functions can be chosen freely and controlled automatically; Comparing with the other common electric water heaters, it has the advantages of energy saving up to 75% and energy efficiency rating above 4 times when making hot water independently; no electricity consumption for getting hot water, energy double sufficient use and energy efficiency rating above 6 times when combi-performing of water heater & air condition as the system recycling use the heat released from the refrigerating process of the air condition to heat the water