Siemens Pressure Independent Control Valves (PICVs) are '3-in-1' devices that combine a control valve, an automatic differential pressure regulator, and a flow limiter into a single unit.
They are primarily used in HVAC hydronic systems (chilled water or hot water) to ensure that the flow to a coil remains constant regardless of pressure fluctuations in the rest of the building's piping network.
Core Advantages
• Full Stroke Control: Unlike many competitors, Siemens PICVs maintain their full valve stroke even when the maximum flow is preset to a lower value. This provides higher control resolution and prevents 'hunting' by the actuator.
• Dynamic Balancing: They eliminate the need for traditional manual balancing valves. If you add a new branch to the system later, you don’t need to re-balance the existing valves.
• Energy Efficiency: By preventing over-supply to coils, they optimize the Delta T (Delta T), ensuring chillers and boilers operate at peak efficiency. This can reduce HVAC energy consumption by up to 25–30%.
• Simplified Sizing: You only need to know the required flow rate (GPM or m^3/h) to select a valve, rather than calculating complex C_v values and valve authority.