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Apartment Radiator Help!!!

Sorry this is long but i want to give a detailed description....I live in the northeast where it has been extemely cold lately, so I decided to turn on my heat for the first time in the 2 years I have lived here. I live in a small apartment in a 4 story building and my apartment has steam (i think) radiators. The radiator has one long pipe on the side. At the top of the pipe is a black knob that says open/close. I turned the knob to open to turn on the heat. When it started to get too hot I closed it. Everything was fine. The next night i went to open it again and I must have either opened it too far or the nut thing below the knob came loose because the whole knob shot off and steam shot up in the air like a fire hose. It scared the crap out of me. I quickly screwed the knob back on and kept it closed. It was fine the whole night. Now today all of the sudden the radiator started hissing and steam was coming out. I figured I must not have closed it all the way so I tried to turn it closed and it just spun around, didnt tighten or anything. I literally had to hold the knob down because i was afraid if i let go the whole thing was going to blow off again. I realized that the nut below the knob was loose so i tightened it as far as it would go which then allowed me to close the knob tightly. However, now it keeps hissing off and on. It will hiss for a few minutes and then stop, and then start up again. No steam is coming out and everything is as tight as it will go (I dont have a wrench so i used my hands) but it sounds like their is still air leaking out from around the nut beneath the knob. I live by myself and I am completely clueless about radiators. Is this hissing/whistling dangerous? can it explode? lol. I dont know what to do because its sunday and maintenance wont be able to come look at it today. Any suggestions??? Should I try opening the knob and letting some air/steam out and then closing it again? Any help would be greatly appreciated.


  • RodRod Posts: 2,067
    Loose Radator Valve

    Hi- You're okay! It won't "explode " or anything like that. What you are hearing is leaking steam which is probably a result of the nut needing to be tightened or needing new packing around the valve stem,   DO NOT HANDLE the valve with your BARE HANDS as steam is invisible and can cause a very bad burn!.  The steam in the radiator is very low pressure (less than 2 PSI) and is what is causing the "hissing"  Have the maintenance people look at it tomorrow

    - Rod
  • shitzngigglesshitzngiggles Posts: 2Member
    Think I fixed it?

    Hi Rod. Thank you for your response. I think I was able to fix it. I noticed that the nut did not appear to be screwed down all the way even though I could not turn it any tighter. So, turned the cap to the open position like I was turning on the heat and this allowed me to screw the nut the rest of the way down. I then closed the cap back up. Its been over an hour now and I havent heard any hissing whereas previously it was almost constant. Hopefully Im good from here on out. Thanks again!!
  • Charlie from wmassCharlie from wmass Posts: 4,068Member
    you are working the radiator at the wrong end

    the valve should be left open at all times. The vent is what is used to control the heat.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • High Pressure?

    The pressure in your system seems very high, it should't have enough power to blow off the valve. It is fine to use the valve to operate the radiator. If it is only a single pipe radiator just remember you have to open the valve all the way for it to work properly. if you have a two pipe radiator you can open the valve to whatever level makes your room feel comfortable.
  • Charlie from wmassCharlie from wmass Posts: 4,068Member
    edited January 2013
    it is not fine to use the valve

    closing the valve can lock the condensate in the radiator. It can also lead to a flooding situation if the condensate builds up in the radiator you think is closed off until it starts spurting out the air vent.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
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