Two-stage coupling heat pump heating system is a set of integrated heating system formed by organically coupling low-temperature air source heat pump and water source heat pump through buffer water tank. Its full name is "distributed air source-water source coupling heat pump heating system (hereinafter referred to as two-stage coupling heat pump heating system). This system is a new generation of HVAC system developed to solve the problem that single low-temperature air source heat pump cannot realize high-temperature heating in severe/cold areas.

When the two-stage coupling heat pump heating system is running, the low-temperature air source absorbs heat from the air as the primary heat source, heats the stratified buffer water tank, and generates 15-30 ℃ low-temperature water; the water source acts as the secondary heat source, absorbs the low-temperature water in the stratified buffer water tank The heat of the water, through secondary compression, provides hot water up to 70-120 ℃ for the terminal system. The first-level low-temperature air source heat pump and the second-level water source heat pump operate through the coupling of the layered buffer water tank to realize the "two-stage compression" of the heat pump, breaking through the technical problems of high-temperature heating under severe cold conditions in the low-temperature air source heat pump industry, and improving the heating capacity, heating stability and system energy efficiency of the system throughout the winter.

Technical advantages of two-stage coupled heat pump heating system:

Two-stage compression resistance to severe cold -36 ℃ stable heating
One of the main reasons for the shutdown of the low-temperature air source heat pump due to severe cold weather is that the compression ratio exceeds the limit value of 11. The two-stage coupling heat pump adopts two-stage compression, even if the ring temperature drops to -36 ℃, through the heat storage effect of the buffer water tank, the first and second compression ratios are intelligently controlled, and the step temperature is raised to ensure that the compression ratio of the two stages is always controlled at about 8, thus realizing stable operation in severe cold environment,

Two groups of refrigerants cross the temperature zone 70 ℃ high temperature heating

The span of the working temperature zone of the refrigerant is limited, and the 1 group of refrigerants cannot directly generate high-temperature hot water in an ultra-low temperature environment. Two-stage coupling heat pump two-stage compression adopts two groups of refrigerants, the first group of refrigerants realize from ultra-low temperature to medium temperature (20~25 ℃), the second group of refrigerants realize from medium temperature to high temperature, and the two groups of refrigerants relay in temperature zone, so as to easily realize high temperature heating at -36 ℃ and 70~120 ℃.