What type of vent is this?

Options

Hello,

The vent shown in the attached image is on the front of a recessed steam radiator. It is a one pipe system. After testing my system, I noticed the vent was letting steam out of it. I think I need a new vent, but not sure what type of vent is it and if I screw the whole piece off or just a part of it? It’s different than the other vents I have on my other radiators.
Thanks for the help.

Comments