Optima Compact

The valve will guarantee the stated flow, if the pressure loss over the component is within the following intervals:

DN10-15 (low):              Δp = 16-800 kPa
DN15 (high)-DN25L:      Δp = 20-800 kPa
DN32-100:                     Δp = 30-800 kPa

For pump dimensioning, a pressure loss of 16, 20 or 30 kPa can be expected, in relation to the intervals above.

If the flow e.g. is set to 3000 l/h, and a Optima Compact DN32 is selected, a flow of 3000 l/h will be maintained as long as the pressure loss is adjusted to the interval 30-800 kPa.

Data sheet


Frese OPTIMA Compact

Pressure independent control valve

Designed to combine automatic balancing and full modulating control regardless of the preset flow.

The innovative design of Frese OPTIMA Compact introduces an intelligent control valve that adjusts automatically to the preset flow in order to provide full modulating control. When the installer presets the valve according to the maximum designed flow, the stroke of the control valve remains the same thus providing 100% modulating control.

In practical terms, Frese OPTIMA Compact ensures that there is no overflow and that below the design flow the actuator has absolute authority. Furthermore, Frese OPTIMA Compact combines all those features that are necessary to ease the work of designers and installers:

  • The wide (up to 800kPa) differential pressure range meets the requirements of most applications
  • The compact design and the user-friendly presetting unit guarantee easy installation and commissioning.

Frese OPTIMA Compact pressure independent control valve (PICV) is used in heating and cooling systems with Fan Coil Units, Chilled Beams or other terminal unit applications. Frese OPTIMA Compact provides modulating control with full authority regardless of any fluctuations in the differential pressure of the system. It combines an externally adjustable automatic balancing valve, a differential pressure control valve and a full authority modulating control valve. 100% control of the water flow in the building is achieved easily, while creating high comfort and energy savings at the same time.

An additional benefit is that no balancing is required if further stages are added to the system, or if the dimensioned capacity is changed. Energy saving due to optimal control, lower flow and pump pressure. Maximized ΔT due to faster response and increased system stability.

Frese Academy – Learn more about Frese OPTIMA Compact Actuators


  • Less time to define the necessary equipment for a hydraulic balanced system (only flow data are required)
  • No need to calculate valve authority. Always one.
  • Flexibility if the system is modified after the initial installation