Pressure reducer for drinking water pipes - what you should know

In this article you can read about what a pressure reducer is, what it is used for and why you need it at all. In addition, you will learn everything you should know about the correct installation and setting of the pressure in the pressure reducer.

Task of the pressure reducer

The water suppliers deliver the drinking water into the house with a very high supply pressure in order to be able to supply very long pipe networks. A certain water pressure in the pipes is also necessary inside the house in order to ensure an adequate water supply even on higher floors.

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The supply pressure of the water is usually much higher than the pressure, because house installations would withstand in the long term. It can be up to 10 bar. Inside the house, however, only 2 - 3 bar pressure are required.

The pressure reducer installed at the transfer point, which, by the way, must be installed, reduces the high supply pressure to a value suitable for the house installation. This value is usually around 2 bar and an additional 0.5 bar for each existing floor. However, the values can vary slightly in individual cases.

Problems with excessive pressure

All built-in devices, such as boilers and fittings, are pressure-sensitive. In the idle state, fittings can only withstand a pressure of around 5 bar without damage in the long term.

Control variable

The control variable in the pressure reducer is the so-called back pressure - not the incoming water pressure, but the water pressure behind the pressure reducer. If it is too high, a valve closes; if it is too low, a valve opens a little to let more water through.

Important installation instructions

The dimensions (in m / s) must be correct. For house systems with sound insulation, 2 m / s apply, without sound insulation 5 m / s. This has to be coordinated with the respective nominal size. Shut-off valves must be provided, the sieve cup must always point downwards when installing in horizontal pipelines. The pressure gauge must also be clearly visible.

Tips & Tricks Pressure reducers must be checked annually for their function and control behavior. This must be done by a qualified specialist. The spring, diaphragm and control valve should be replaced every 2-3 years.