Automatic Air Vent Leaking

The air vent is leaking some water.
Automatic air vent leaking. Hi, i have an automatic air vent above our boiler that has never really done anything automatically and has now developed a leak. Automatic air vent model no. Automatic air vent hygrovent article number size unit 2280c18x 1/8 100 2281c14x 1/4 100 2282c38x 3/8 100
This made me look for an issue and the automatic vent valve appears to be leaking. It appears to be a 1/2 inch connector. Pressure in expansion tank was low so opened both valves in loop and added water till pressure 1.5, meanwhile automatic air vent has started leaking and expansion tank pressure is dropping.
About 2 bar every week or two. Bell & gossett's line of manual and automatic air vents are designed to remove troublesome air in the system. Status not open for further replies.
Installed on water or stream radiators the taco automatic coin vent is the ideal air purging device. Taco automatic air vents include: When air becomes trapped in a sealed heating system it can cause a wide variety of problems including excessive noise, corrosion and increased maintenance costs as it also can cause air locks and prevent the system from operating effectively and efficiently.
0253020 3/4” 0253025 1” 0253032 1.1/4” part no. The coin vent features special hygroscopic cellulose discs in the valve body that, when dry, allow air to be released from the system. This wasn't noticed until it had somewhat flooded the cabinet and dripped through to the area where the pump is located;
When dry the discs allow air to be released from the system. Then after trying to stem the flow (cap is missing) water began to pour. Size the maxivent valves are inspectable thanks to the opening left by the cover after unscrewing it from the tank;