Pressure Independent Control Valves and Actuators

Pressure Independent Control Valves

Pressure Independent Control Valves (PICV) make a significant contribution to efficient energy usage and offer cost savings by preventing over- or under-supply of heating or cooling energy. They also improve the control accuracy and, therefore, enhance room comfort.

Siemens’ PICV portfolio is comprised of:

  • 19 different valves from 0.5" to 3" covering a flow range from 0.2 gpm to 190 gpm and with a differential pressure operating range from as low as 2.3 psi to as high as 90 psi.

  • 10 different actuators providing floating and 0-10V proportional control with fail-in-place or fail-safe operation.

Siemens’ PICV integrate three functions into a single device: control valve, adjustable flow limiter, and automatic pressure regulator. Siemens’ PICV unique selling points include:

  1. A control valve for temperature control

  2. An automatic differential pressure regulator for balancing pressure fluctuations in the hydronic system, and

  3. An adjustable flow limiter (not available on most competitive valves) for setting the required flow rate.

  • The full stroke of the valve is always used regardless of the maximum flow setting. Competitors reduce the flow with a fixed limiter and/or by limiting the stroke of the actuator.

  • The automatic differential pressure regulator operating range is from as low as 2.3 psi to as high as 90 psi. Most competitive products require at least 5 psi for proper pressure independent operation. This lower minimum differential pressure allows the system pumps to be turned down more, resulting in less wasted pump energy and higher savings than required by competitive pressure independent control valves.

  • Optional P/T ports kits are available for measuring the differential pressure across the threaded valve body.  P/T ports come standard on the flanged valves.

  • Free valve tagging on all valves and assemblies.

Features

Functions

Benefits

Pressure independent sizing

- Eliminates need for calculating Cv using flow and pressure drop.

- Simplified valve sizing.

Adjustable flow limiter

- Analog scale provides flexible adjustment of maximum flow allowed through the device.

- Eliminates over-supply.

- Locking nut prevents accidental changes to maximum flow setting.

- Energy cost savingsOptimized performance.

- Simplified balancing for fast and trouble free commissioning.

- Commissioning cost savings.

Mechanism for maximum flow setting is independent of valve stroke

- Always maintains full stroke of valve.

- Greater control resolution and precision

- Excellent control accuracy.

Stroke valve design

- Uses standard Siemens SS Series, SQS, SAX, and new SQV globe valve actuators.

- Eliminates deadband associated with ball valve actuators at beginning and end of stroke.

- Common actuator wiring simplifies installation.

- Greater control over the whole stroke of the valve and actuator.

Automatic pressure regulator

- Automatic balancing and pressure independent
- Maintains constant flow through the valve at any given control setting regardless of the pressure fluctuations in the system.

- Always maintain maximum valve authority.
- Avoid over- and under-flow.

- Energy cost savings
- Easier balancing and shorter commissioning times.

- Commissioning cost savings.

- Eliminate “hunting”, increased actuator life due to fewer repositions.

- Greater comfort due to better control.

Automatic balancing

- Adjustable flow limiter and automatic pressure regulator automatically balance the system loop.

- System expansions do not require re-balancing of existing system.

P/T Ports

- Measure differential pressure across the device.
- Standard on flanged valves.
- Optional accessory kit for threaded valves.

- Easily validate that the device is operating in the design range for pressure independent functionality.

- Saves time troubleshooting problems.

Proven Actuator families

- Familiar, rugged and reliable Siemens actuators have been installed in well over a million applications worldwide.

- Ensure highest levels of customer satisfaction.


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