Renner's safety valve is suitable for use in boilers and is designed to protect central heating systems from dangerous overpressure. When the pressure exceeds a preset value, the valve automatically opens, allowing the system to be depressurized. This function is essential for the safety of the installations, as high pressure can cause serious risks to people and materials.

The Renner VS1220PED4 is a double-port valve, meaning it has two ports—one for the inlet of the medium and one for the outlet. When the inlet is closed, the flow is interrupted, while when open, the flow at the inlet and outlet is the same. This valve is installed at the highest point of the installation, ensuring reliable operation without the need for additional switches or valves.