To transport liquids or gases in a pipe system, pressure is required. Without this it is not possible to move the materials over long distances. Therefore, water pipes are always under high pressure so that the liquid can easily reach all connected households and buildings. However, it can happen that this is too high in the supply line for the components that are connected inside the house. As a result, they are damaged or even burst. This can result in severe water damage, which entails considerable costs. Therefore, it is common in sanitary engineering to use water pressure regulators. These are small components that can be easily installed between the individual pipes. They always lower the pressure to a fixed value, regardless of how high the inlet pressure is. The pressure reducer can be installed at the beginning of the system to reduce the pressure throughout the house. It is also possible to install it in the areas that are intended for the connection of such household appliances that can be connected directly to the water pipe. These include, for example, dishwashers or washing machines and some fully automatic coffee machines. This prevents the sensitive devices from being damaged by excessive pressure. It is also possible to use a corresponding reducing valve for the heating system or for an irrigation technology.
How the water pressure regulator works
Inside the device for reducing the water pressure there is a membrane and a valve. Both components are mechanically linked to one another. The valve is in the direction of flow in front of the chamber in which the membrane is attached. This is used to control the valve. On one side the pressure of the line acts on it, on the other side a spring is attached to counteract this force. When the pressure in the pipe increases, the membrane expands. This movement changes the setting of the valve and causes it to close a little. This reduces the pressure in the area behind the valve. The two components are matched to one another in such a way that they always generate a constant pressure in the outlet area of the device regardless of the inlet pressure. It is important to make sure that these items are designed for use on clean water only. Filters are necessary if the water is contaminated. Special gas pressure reducers are required for gas pipes.
The water hammer arrester as an alternative and supplement
An excessive high pressure in the water pipe is not always due to too high an inlet pressure. It can also happen that this arises internally. This is due to the phenomenon of water hammer. If the liquid moves quickly in the pipe and is then suddenly braked by a valve, the kinetic energy leads to a very high pressure being created. This can severely damage the cables. Ordinary pressure valves do not offer a solution to such problems. A special water hammer arrester is required for this. You can also easily integrate this into your line. It consists of a hollow body with a membrane inside. If the pressure suddenly increases due to the water hammer, this membrane expands. This causes the pressure inside the lines to drop, which prevents damage.
One of the essential selection criteria when buying a water pressure regulator is the control pressure that the device generates. This value indicates how high the pressure is in the outlet area of the device and thus in the lines connected to it. Another important aspect is which material is used to manufacture the housing. For example, there are models that are made of plastic. This material is not only characterized by the fact that it is quite inexpensive. It is also very moisture-resistant. It is also comparatively robust, so that it can easily withstand the pressure in conventional water pipes. Another alternative is to use a brass model. The metal products are much harder than plastic valves. For this reason, they are suitable for a higher operating pressure. In addition, the corresponding articles are very resistant to many other mechanical loads. The brass is nickel-plated to guarantee good rust protection. The choice of material is not only of great importance with regard to the operating pressure, but also with regard to the temperature of the medium that is to be regulated here. While plastic pressure reducers are only suitable for cold water, you can also use brass articles for hot water pipes. The materials used for the seals and the membrane also differ. Another important consideration when purchasing a pressure relief valve is the size of the ports. Models with 1/4", 1/2" or 3/4" are available. It is of course ideal to always select the same diameter as the piping, but should this size not be available it is also possible to adjust the sizes accordingly with the help of reducers.
Important features of the individual pressure regulators:
- Value of the pressure generated by the device
- operating pressure
- different materials for housing, membranes and seals
- Media temperature for which the valve is intended
- Connections size