For Optimum HVAC system performance and energy efficiency/ savings we need the below: The chilled water system to be hydronically balanced at full load (DRV or manual balancing) at partial load (DPCV). Improving control valve characteristic WITH optimum authority for high efficiency exchange between water & air thus bringing delta T to the design value this will only be achieved by eliminating system pressure fluctuation effect on the control valve throttle / stem. In order to have all above features combined in one valve Danfoss is offering PRESSURE INDEPENDENT BALANCING & CONTROL VALVE.