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Inlet valve banging when closed, hissing when open
On the top/4th floor of a 100 year old apartment building in NYC with a one-pipe system.
One of my steam radiators does something a bit funny.
When the inlet valve is closed, I'll hear a banging when the heat comes on, sounding like it's coming from the pipe/inlet valve area itself. I'd thought that this steam/water banging noise could only happen when the valve is open. And yes, I'm definitely closing the valve fully and tightly.
On the flipside, when the valve is open, occasionally there's a hissing noise that sounds like it's coming from the inlet valve itself - you can see a video of it here: <a href="https://www.dropbox.com/s/srxw4uzss8no46z/2014-04-01%2023.54.00.mp4">https://www.dropbox.com/s/srxw4uzss8no46z/2014-04-01%2023.54.00.mp4</a>
Also, when I close the valve on a hot system (because the hissing is driving me nuts) just a few drops of water drip out of the pipe that feeds into the radiator itself.
The super is mostly uninterested, any ideas on what I can do?