1. Multi-source utilization: domestic hot water (55℃) or heating can be prepared under two different working conditions, applicable to both the working conditions of air source (-10 ~ 43℃) and water source (7 ~ 40℃). 2. Flexible application: the application can be selected according to the conditions. When the environmental climate or water source conditions are both available, the water source side heating in spring and summer, the air source side heating in autumn and winter, and the water source side heating in autumn and winter are available; 3. High efficiency and energy saving: high energy efficiency ratio. In spring and summer, the whole cold recovery and heating at the water source side provides a certain amount of cooling for the refrigeration system, with COP values up to over 7.0 on both sides and an average of about 3.5 in winter. Widely used: mainly used for large commercial enterprises, widely used in the preparation of domestic hot water or heating in the central air conditioning system with water cooling or in hotels, hotels, conference centers, apartments and villas beside rivers, lakes and reservoirs; 6. Cost saving: Less investment and less energy costs. The dual-source heat pump water heater is a combination of the air-source heat pump water heater and water-source heat pump water heater. 7. Stable performance: Seiko manufacturing, high-end configuration, the use of brand product components. 8, beautiful and durable: the unit structure is reasonable, the shell adopts 304 stainless steel is not easy to rust, the unit life of more than 10 years.