Bypass valves
Product Stage Picture ByPass Ventil

Application areas



Product range

OEM/Industry name="column1"
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The HDS (hydrodynamic switch) valve is a dynamic overflow valve. By maintaining a defined differential pressure, it ensures constant pressure ratios in special components of boilers and sensor faucets.

There are two application areas by way of example:
In water-driven mini-turbines of electronic 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.

In hydraulic assemblies of boilers

HDS valves limit the delivery pressure of DHW circulation pumps and ensure a minimum flow rate in the boiler circuit. They also avoid annoying flow noise caused by excessive differential pressure.

Quality features

Function and installation

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.

HDS closed

Constant flow at defined differential pressure

HDS partly open

Excess water passes through the HDS bypass valve

HDS fully open

Even more excess water passes through the HDS valve

Selection criteria

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.


All relevant technical data on NEOPERL HDS bypass valves is available for download here. Other models are available upon request.

Get advice now

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.

OEM / manufacturers
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