The Caleffi safety valve is ideal for boilers, providing reliable protection for central heating systems against overpressure. When the pressure exceeds a set value, the valve opens to release excess pressure from the system, preventing serious safety hazards and damage to the installation. It is installed at the highest point of the system and operates automatically without the need for a switch or manual valve.

The valve's design includes two ports: one for inlet and one for outlet. When the inlet port is closed, flow stops, and opening the inlet port ensures that the flow through the outlet remains equal to that at the inlet.