Vaillant's Automatic De-Aerator is a device designed to efficiently remove air and other gases from the heating system, ensuring optimal performance and preventing issues such as airlocks and reduced efficiency. This essential component contributes to the smooth operation of Vaillant heating systems, enhancing overall reliability and functionality.

A central heating safety device, the air vent releases built up air. As water flows through the system, a float opens or closes the vent depending on the water level. When the system is full the float is pushed to the top, closing the vent until the water level drops.