The central heating filling valve, also called the central heating filling valve or filling valve, is an important element in the heating system. Its main function is to supply water to the central heating system to enable the correct operation of the entire system. How does such a filling valve work? Check out the article!
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How does the fill valve work?
The filling valve for the central heating system is a key element that allows controlled filling of the system with water and maintaining the appropriate pressure in the heating system. The main function of this valve is to supply water to the central heating system. During the first start-up of the system or after topping up the system with water (e.g. after replacing parts of the system or after a period of inactivity), the filling valve is opened, allowing water to flow into the heating system. Water fills the entire system, including pipes, radiators and other elements, preparing it for proper operation.
The filling valve is equipped with pressure regulation mechanisms that allow you to control the amount of water supplied to the system. This allows you to maintain the appropriate pressure in the heating system, which is crucial for its efficient and safe operation. The filling valves are also equipped with mechanisms 
safety valves that protect the installation from overfilling with water. Once the appropriate filling level is reached, the filling valve automatically closes to prevent further water inflow.
Some filling valves are equipped with pressure gauges that allow the user to monitor and control the pressure in the system. This allows you to quickly notice any pressure changes and take appropriate action. It is also important that the filling valve is properly selected for the needs of the specific central heating system and is installed in accordance with the safety rules and requirements. Thanks to the correct operation of the filling valve, the central heating system will operate efficiently, providing heat to all rooms in the building.
How to fill the central heating system?
Regular refilling of the central heating system is crucial for the proper functioning of the entire system. At the same time, observed deficiencies are information about a possible leak. How to carry out the entire process?
The first step is to turn off the central heating system and then locate a special filling point. Remember to close all valves for a given circuit, which allows for accurate and even filling.
Water leaking through the filling valve should not exceed the specified technical standards. Hissing coming from the tank may be a signal that the structure is full and that pressure stabilization manipulations have begun.
TOP 5 best filling valves
We already know that the filling valve plays an extremely important role. That's why we have prepared a ranking of the best products!
Afriso FAM filling valve with pressure gauge
The Afriso FAM filling valve with a pressure gauge has a pressure limiter, a non-return and shut-off valve, and a pressure gauge. This will allow for more efficient use of the valve. Additionally, the valve has a GW connection, and the maximum temperature in the central heating pipes is 90 °C
Resideo Braukmann filling valve with GW 1/2"/GZ3/4" connection
The Resideo Braukmann VF 06 filling valve is designed for filling and topping up closed heating systems with water. The valve contains a pressure regulator, a non-return valve and a shut-off valve. The valve design allows for the installation of a manometer to measure and control the pressure on the system side. The use of the VF06 allows you to avoid damage that may occur due to excessive pressure when filling the system.
Filling valve SYR 2128 3/4"
The SYR 2128 3/4" filling valve is designed for closed water heaters and tanks. It consists of a shut-off valve, a non-return valve with a control nozzle, a nozzle for connecting a pressure gauge, a safety valve 2115 (replaceable stainless steel seat) with a discharge basket. Thanks to these parameters, the use of this valve will work well in a central heating installation.
Ferro ZN15 1/2" filling valve
The Ferro ZN15 1/2" filling valve is a reliable device with outlet pressure regulation (1-4 bar), maximum inlet pressure (10 bar) and maximum operating temperature (80°C). It has a 1/4" pressure gauge connection and is easy to install thanks to the screw connection. It is an ideal solution for comfortable and safe filling of heating systems.
Flamco Flexcon PA AutoFill filling valve
The Flamco Flexcon PA AutoFill filling valve records and alerts in the event of pressure problems and helps to set and control the correct system operating pressure. The assistant also informs about the expected service life of the expansion tank without disconnecting it, and the user can configure monitoring of maintenance intervals for third-party components. This makes it even easier to detect potential problems in the central heating system.