We live in an NYC apartment with steam heat. The noise of this radiator is driving us crazy because it's in the bedroom. We want to turn it off. The solution seems to be to shut the intake, the same way you would if you wanted to separate this unit from the system to service it. However, this set-up doesn't look quite like any of the instructions on turning off radiators that I've found online.
My question is: How do I close the intake on this radiator?
What I tried
I tried turning the screw on the right hand side clockwise, and it appeared to tighten, but did not shut off the intake. I tried taking a pair of pliers and turning the nut underneath the screw clockwise (very stiff), but I stopped when it seemed to start leaking steam around the top of the nut (and turned it counter clockwise a turn or so to undo).