How do I shut off a National Art Convector?

legular

We recently moved into an older home and every convector is the same model 5405 National Art Convector from National Radiator Co out of Johnstown PA. They seem to be working fine except one in the bathroom that vertical valve piece on the right is wildly corroded and slightly leaking. I've attached pictures of one in better condition, and I'm just looking for guidance on how to shut it off and stop the flow of water through it until we can have a service technician out to inspect and repair it.

Thanks!

JUGHNE

It looks like it has no valves to stop the flow.

The item on the top of the riser pipe on the right is a manual air bleed valve.

It has a screwdriver slot or a square head to open and close for air removal.

It may have to be replaced and might require draining down the system at least part way.

You might look at all the others and see if any are corroded up and not moveable and resealable.

Change any that are suspect.

legular

Thank you kindly!