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How to fix this leaky valve?

Hi all, I live in an NYC coop and the previous owners removed a radiator and left just the closed radiator valve (see photo) in the floor. As the heat has been on more frequently, the valve has been leaking a small amount of steam and creating a whistling sound. The source of the leak is definitely that the rubber washer meant to close the valve is deteriorated.

Is there anything else I can do to stop the leak aside from either replacing or removing and capping the valve?


  • Jamie Hall
    Jamie Hall Member Posts: 23,303
    Theoretically the best approach would be to replace the deteriorated washer. However, don't do it. Just don't. Why? Because Murphy is alive and well in your building, and about the same time you got the valve apart the boiler would come on, and uncontrolled live steam is just no fun at all.

    Instead, if you can get a threaded cap to match that union thread, which may not be all that simple, you could put that on with some teflon tape. However, as I say, that's half of a union and I doubt that you will find a cap to match.

    Try this (I know this will sound tacky, but it will work). cut a square piece of something stiff -- quarter inch plywood, maybe -- exactly as wide as the diameter of the outside of the threads. Put a piece of rubber on one face of it. Cut away enough of that misguided flooring so that the piece will fit squarely on the opening. Take a screw type hose clamp and wrap it around the back of the valve and your piece of whatever, and tighten it up.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • pecmsg
    pecmsg Member Posts: 4,851
    edited December 2021
    That valve is part of the building. As such notify the building of an unsafe condition, during the next scheduled shutdown it can be capped. 
    mattmia2Alan (California Radiant) Forbes
    JUGHNE Member Posts: 11,061
    I have heard of the wood alone, without the rubber, would seal when it got wet and expanded.
    EBEBRATT-Ed Member Posts: 15,527
    edited December 2021
    looks like the pipe took a nose dive when it was disconnected.

    @sofimarshall If by chance you know where the old radiator is you could take the pipe stub off the radiator and put it back on the valve with a pipe cap

    I would call maintenance it should be their problem.
  • bburd
    bburd Member Posts: 918
    That open valve is a serious safety hazard and code violation and should be repaired promptly.

  • Alan (California Radiant) Forbes
    Maybe that's the steam room that was in the advertisement for the apartment.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab