The HDS (hydrodynamic switch) valve is a dynamic bypass valve. By maintaining a defined differential pressure, it ensures constant flow conditions in special modules of boilers and sensor faucets.

By keeping the pressure loss at a constant level over a certain flow rate range, HDS valves ensure smooth turbine operation for power generation.

HDS valves limit the delivery pressure of circulation pumps and ensure a minimum flow in the boiler circuit. They also avoid annoying flow noise caused by excessive differential pressure.
HDS bypass valves open as soon as the water pressure reaches a level defined by means of the force of the installed spring.
The more water flows, the wider the valve opens. The excess water is diverted past the main pipe with the device (pump or turbine), where the pressure and flow rate remain constant.
HDS bypass valves are installed in the flow direction.
Please note that bypass valves are only available for our OEM / manufacturing customers. For more details, as well as information on worldwide approvals, please see the product listing. To refine your selection, please use the following points as filters.
Do you need help choosing? You will find the relevant contact information towards the bottom of the page.

- Part No. : 304903000
- Bore diameter: 15.2 +/- 0.1 mm
- Pressure drop: 300 mbar

- Part No. : 304906000
- Bore diameter: 20.2 +/- 0.1 mm
- Pressure drop: 400 mbar

- Part No. : 304907000
- Bore diameter: 15.2 +/- 0.1 mm
- Pressure drop: 250 mbar

- Part No. : 304909000
- Bore diameter: 15.2 +/- 0.1 mm
- Pressure drop: 190 mbar

- Part No. : 304911000
- Bore diameter: 15.2 +/- 0.1 mm
- Pressure drop: 500 mbar
- Part No. : 304912000
- Bore diameter: 15.2 +/- 0.1 mm
- Pressure drop: 17 mbar

- Part No. : 304913000
- Bore diameter: 15.2 +/- 0.1 mm
- Pressure drop: 78 mbar

- Part No. : 304914000
- Bore diameter: 15.2 +/- 0.1 mm
- Pressure drop: 450 mbar

- Part No. : 304915000
- Bore diameter: 15.2 +/- 0.1 mm
- Pressure drop: 950 mbar

- Part No. : 304916000
- Bore diameter: 15.2 +/- 0.1 mm
- Pressure drop: 800 mbar
All relevant technical data on NEOPERL HDS bypass valves is available for download here. Other models are available upon request.
Please contact us for help finding the right bypass valve. Neoperl offers you solutions that are completely tailored to your requirements. Our qualified staff will be happy to assist you with any questions you may have.
