Everything You Need to Know About Water Control Valves

Water in pipes is under a certain pressure, which is crucial for the proper functioning of the distribution systems. If the water pressure is too low, too high, or fluctuates, it can cause significant problems. Control valves are used to regulate and stabilize water pressure, protecting your equipment and appliances from excessive mechanical stress and ensuring efficient and economical operation of the system.

What are control valves and what is their function in water systems?

Water control valves adjust the amount of water flowing through, and thus the pressure in hot water heating systems. You simply set the desired output pressure, and the control valve takes care of adjusting the input pressure according to your specified parameters.

Some control valves also serve to shut off, distribute, and mix the flowing water. This allows them to control not only flow and pressure but also the temperature of the output medium. Control valves are used not only in domestic heating systems but also in industry.

Advantages of control valves for heating

Control valves ensure even distribution of the heat-carrying fluid at all consumption points, thus providing thermal comfort without unnecessary costs. At the same time, they protect the system from excessive mechanical wear caused by high pressure. This ensures safe, efficient, and economical heating operation.

Control valves are especially used in multi-storey buildings where it is necessary to ensure sufficient pressure even at higher consumption points. However, pressure can be unstable for many other reasons, such as fluctuations in water consumption during the day, undersized connections, extensions or other expansions of the house that the original distribution project did not account for, etc.

What is the difference between a control valve and a pressure reducing valve?

Control and pressure reducing valves are often confused, but they are not the same:

1. Water control valves adjust the amount of water flowing in the pipes – they can therefore increase or decrease the pressure. Their function is to stabilize pressure and protect against both high and low water pressure.
2. Pressure reducing valves are installed on domestic or apartment water connections and, as their name suggests, serve to reduce and stabilize the water pressure supplied from the water main. Their function is to protect pipes and appliances from excessive stress, as well as to reduce water consumption and system noise.

Siemens control valve with actuator

Types of water control valves

There is a wide range of different types of control valves on the market for adjusting water pressure. They can be divided, for example, by control method:

• Control valves with manual control are adjusted using a wheel. They are intended for smaller circuits, such as small heaters and coolers or apartment distributions.
• Lift control valves for water are automatically controlled using an actuator. Lift valves are used for family homes and larger applications, such as in boiler rooms or industry.

They are divided into two-way and three-way based on the number of inputs and outputs. Two-way water valves have one input and one output, thus regulating flow and pressure on one pipe. Three-way water valves are also used for mixing or dividing flows. They are mainly used for mixing cold and hot water, where they regulate not only flow and pressure but also the temperature of the output water.

How to choose a water control valve

The basic parameters, besides the type of valve (two-way or three-way) and its control (manual or automatic), include the type of medium. Control valves for water are generally not compatible with other types of media. The type of water is also important, whether it is potable water, hot water, or heating water. If you are looking for a control valve for heating or hot water distribution, also focus on the operating temperature range of the control valve.

Depending on the type of water and application, choose the appropriate valve dimension and manufacturing material – this is important for maintaining the required hygienic standard and preventing corrosion. Other parameters when selecting include maximum flow and pressure or type and size of connection. The most common are external threads, but for larger valves intended for more demanding applications, flange connections are used, which have high tightness and reliability even at high flow and pressure.

Robust three-way water valve Belimo

Installation and maintenance of control valves

Installation is carried out according to the type of connection, but always according to the direction of flow, which is marked on the valve. Follow the manufacturer's instructions and observe safety precautions during installation.

Control valves are maintenance-free, but to prevent damage, we recommend installing a mechanical impurity filter before the valve. Mechanical impurities can clog the valve, shorten its lifespan, and reduce its functionality. The water filter needs to be regularly cleaned by flushing to prevent clogging.

Need advice on choosing the right water control valve? We provide expert advice to our customers free of charge. Do not hesitate to contact us.