Pressure Independent Control Valves or Pressure Independent Balancing and Control Valves – also commonly known as PICVs (or PIBCVs) – are getting more and more popular in both 2- and 4-pipe heating and cooling applications due to their accurate flow control at any load condition.
A PICV includes three valves in one body by combining the control function, the balancing function and differential pressure control function in one unit.
• Control
The control function of the PICV, as with any other 2-port control valve, allows load dependent flow variations from selected design flow (100% load) and down to closed valve (0% load). By varying the flow rate, the heat output of the terminal unit is controlled and will provide optimal room comfort. The key to the optimal solution is to choose a true PICV with 100% authority using full stroke or multiple rotations when regulating to reduced flow rates.
• Balancing
The key to the optimal solution is to choose a real dynamic balancing valve including a rolling diaphragm which at any time will self-balance to the required flow independent on system pressure changes. The balancing function shall be easily adjustable to several max. flow settings (minimum 41 different) in the same PICV.
• ΔP control
With changing load requirements in the system, system pressure will also var. This calls for an automatic balancing solution which instantaneously compensates for the pressure changes by adjusting the flow outlet with the rolling diaphragm as described above under balancing.

Application
The FlowCon Green.3 is designed to facilitate large fan coils, smaller air handling units, smaller heat exchangers or equivalent. In general, it is the optimal choice in any applications where efficient distribution of water - with focus on system pressure drop - is required. In addition, will FlowCon Green.3’s low pressure drop and feedback option will make the valve ideal for Green Building projects.

Application Example
Plate Heat Exchanger with Pressure Independent Control (PICV) - Modulating Control.

100% Authority - Pressure Independent Control Valve
The FlowCon Green.3 valve is a pressure independent dynamic control valve which meets today’s HVAC requirements of reducing building running costs without increasing initial installation costs. The FlowCon Green.3 is an essential partner in the strive for reducing operational cost, energy consumption and CO2 emission.

The valve includes an innovative self-adjustment feature allowing continuous mechanical self-balancing in all valve positions. Next to this, the valve is constructed in such a way that the valve stroke is unaltered regardless which of multiple design flow settings is selected. This ensures that each thermal unit controlled by a Green.3 valve is always supplied with the exact flow required for the specific system condition.

The FlowCon Green.3 valve is a true pressure independent control valve which always holds 100% authority. As long as the pressure differential across the valve is within the operating range, the Kv (Cv) of the valve is changing and continuously regulated to maintain required flow. Any flow below design flow is controlled with full authority via the MS through the valve actuator.