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Plugging steam radiator air vent - apartment way too hot

alan_21 Member Posts: 2
Hey guys, this site has been so valuable in figuring out a way to make my apartment livable. The landlord has proven to be incompetent in resolving this problem for me so it's time to take matters in to my own hands, I guess.

The situation:

I'm in an old building in San Francisco which has a single pipe steam system. The boiler kicks on about 6 times a day. The valve on the radiator in my apartment is clearly broken, the knob is turned as tightly as it will go and each time the boiler kicks in, the air valve starts blowing and my place gets hotter than I can tolerate. My apartment is getting well over 100 degrees. Recent weather in SF was around 85 degrees. It's too much to handle!

Based on my reading, I should find a way to prevent steam from entering the radiator by replacing the air valves with thermostat valves. I attempted to swap one out at one point in a previous apartment and the housing of the Hoffman 40 separated from the threads and I had water all over the floor, but that's another story. Needless to say, I'm not going to try to pull these things out. They look like they've been in there for a hundred years.

My question:

As a temporary measure to mitigate the boiling heat, wrapped the hoffman #40 vents with tightly wrapped electrical tape. This seemed to do the trick for one of the radiators (it hasn't gotten hot since) but the other one is still getting pretty warm. I can see that the air broke the sticky on the tape and is venting air. I'm looking for a solution to MacGyver this air vent in to no longer venting. Pulling the valve and replacing with a plug or another valve is not an option, and the tape doesn't seem to be holding.  Any ideas?


  • Jamie Hall
    Jamie Hall Member Posts: 18,966
    Can you manage

    to rotate the vent half a turn so that it points down instead of up?  That will usually shut the thing off...

    Course you don't want to break it...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • alan_21
    alan_21 Member Posts: 2
    I considered that

    but it's a terrifying prospect. Last time I turned a valve over, it sheared off in my hand. Needless to say, the floor got very wet.
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,564
    System runs hot in hot weather

    Are you sure the landlord is not willing to save some money on fuel? After all he will be the one to raise the rents, because of the cost of utilities!!

    You have to turn the vent in the unscrewing direction, to get it at the closed stage.

    It seems that the pressure is high enough (much too high), to push the tape off the vent, and allow the steam to make your life a misery. He should be turned into the local Green organization for wasting fuel!--NBC