Check valves in water and heating systems

Check valves play a crucial role in water, heating, and cooling systems. Their primary function is to allow the flow of the medium in only one direction and prevent backflow. Thanks to their simple, mechanical design, these valves operate automatically and require no maintenance; their proper selection and installation directly impact the safety and reliability of the entire system.

How does a check valve work?

A check valve opens when the medium (most often water or water-glycol) flows in the intended direction—the pressure opens the closing element. If an attempt is made to flow in the opposite direction, this element automatically closes. This solution:

protects the system against backflow of the medium,

protects pumps from damage,

prevents pressure and flow disturbances in closed circuits.

Where and when should check valves be used?

Check valves are installed where there is a risk of fluid backflow in the system, which could lead to energy loss, system malfunction, or equipment failure. In practice, check valves are installed:

in water supply systems, usually behind the water meter or pump on the discharge line (maintaining a minimum distance of 30 cm from the water meter),

in central heating systems—behind the circulation pump, on the return line, before the shut-off valves,

in cooling systems and installations using glycol.

FERRO F-POWER check valves can be installed in any position (horizontal, vertical, diagonal), provided that the flow direction indicated on the body is observed. This installation flexibility makes them easy to use in tight spaces.

Design and materials – what should you know when choosing?

F-POWER check valves are available in two material variants, allowing them to be adapted to specific operating conditions:

models with an ABS disc (designation ZZ•V) – designed for operation at temperatures up to 70°C and pressures up to 10 bar,

models with a brass disc (ZZM•V) – can operate at temperatures up to 120°C and pressures up to 16 bar.

The valve body is made of CW617N-4MS brass—the alloy is nickel-free, so it can be safely used in drinking water systems. The spring components are made of AISI 304 stainless steel, and the seals are made of EPDM, which is resistant to high temperatures and exposure to water or glycol solutions.Additionally, the valve can be equipped with a suction strainer that acts as a mechanical filter—it traps contaminants such as sand or sediment, increasing the system’s durability.

Installation Guidelines

Proper installation of the check valve is crucial for its reliable operation. Please note the following:

Installation work should be performed by an experienced installer with the system pressure completely shut off.

The direction of medium flow must match the arrow on the valve body.

The valve can be installed in any flow axis (vertical, horizontal, or at an angle).

Threaded connections should be sealed using Teflon tape or hemp fiber.

Avoid mechanical stress in the system that could affect the valve body—including during tightening and disassembly (place the wrench on the connection’s octagonal face on the tightening side; do not overtighten).

For versions with a suction basket , cleaning the filter does not require disassembling the entire valve—simply unscrew the basket, remove the debris, and screw it back in.

Practical benefits of using FERRO F-POWER check valves

A properly selected and installed check valve offers a number of advantages:

Increased system reliability – eliminating backflow reduces the risk of failure.

Equipment protection – the valve protects pumps, water meters, and heat exchangers from back pressure.

Maintenance-free operation – no need to adjust or control the valve.

Quiet operation – the use of damping elements reduces noise in the system.

Long service life – carefully selected materials that ensure the valve’s resistance to pressure and temperature translate into many years of durability.

Brass check valves are a simple yet extremely important component of hydraulic systems. Their use enhances the safety, efficiency, and durability of the system. When selecting a check valve, it is important to consider operating conditions (temperature, pressure, type of medium), design, and the availability of accessories such as suction baskets.

FERRO’s F-POWER check valves, featuring a plastic or brass closing element, meet the requirements of modern water and heating systems and can be used in both residential construction and industrial installations.

Find more expert advice on the FERRO PRO YouTube channel.

Watch a video about FERRO valves in single-family housing: