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Attic Radiator Spitting

Today I went up to my unfinished attic, which is totally sealed off from my home (and freezing!), and noticed that the valve must be open and because the vent is spitting/leaking it's hot. This will be an issue once we have some ice (melting the roof, etc) I assume, not to mention I don't want to be heating the attic!

I can replace the vent but curious if it's okay to just shut it on at the main valve. I have another radiator I've shut off at the valve, due to it being a kid playroom.

If I do shut it off, is there a good or bad time to do that? If I shut it off while the system is on, water will be stuck in the radiator after it condensates - is that a problem? If I shut the system off to shut it off, how long do I need to wait for it to cool. Same question goes for replacing the vent.


  • You can invert some makes of radiator vents, which will prevent them from allowing air to escape, and therefore prevents steam from entering the radiator. Make sure the radiator is pitched towards the inlet valve which I would keep open.—NBC
  • coreyndstuffcoreyndstuff Posts: 15Member
    I've used Vent Rite #1 in the past, I could just get that and close it, you mean?
  • coreyndstuffcoreyndstuff Posts: 15Member
    Oh invert, as in upside down. That makes sense! I'm pretty new to the vent game - any suggestions on types that this would work with?
  • The Hoffman 40 is one candidate.—NBC
  • Danny ScullyDanny Scully Posts: 1,219Member
    You can also install an 1/8” pet cock/ball valve before the vent and just shut that off.
  • ethicalpaulethicalpaul Posts: 1,110Member
    Why does your unfinished attic have a radiator? Where I come from, unfinished attics should be outdoor temperature
    1 pipe Utica 112 in Cedar Grove, NJ, 1913 coal > oil > NG
  • coreyndstuffcoreyndstuff Posts: 15Member
    I have no idea! I livd in Massachusetts. My only thought is that they maybe thought they’d finish it some day? Perplexing.
  • ethicalpaulethicalpaul Posts: 1,110Member
    I agree with you, very odd! If it were me I’d shut off that line as close to the main line as possible just before it wants to fire to have it as dry as possible.

    But that doesn’t matter much because then I’d disassemble the pipe and cap it!!
    1 pipe Utica 112 in Cedar Grove, NJ, 1913 coal > oil > NG
  • Jamie HallJamie Hall Posts: 11,466Member
    I like @ethicalpaul 's approach! What I would not do is turn the radiator off with its own valve -- as I just noted to someone else, very few steam radiator valves are perfectly tight against steam, and I'd be concerned that a little steam might get in from time to time and condense, and not be able to escape -- and then freeze and bust the radiator.
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • coreyndstuffcoreyndstuff Posts: 15Member
    @Jamie Hall That makes sense. Where it's already getting cold, if I use a valve Petcock/ball will that allow the condensed water to drip back down and not cause issues? That's my current short-term plan until I figure something out in the future. Just trying to stop the problems now as the heating season starts.
  • JUGHNEJUGHNE Posts: 6,224Member
    I think the vent inversion to stop air venting is a feasible solution in a heated room. But in the cold attic, I think still enough steam will get into the rad and possibly be slow to drain back with the vacuum created in the rad by not having a vent to open for air re-entry.
    I would remove the steam line valve and cap it, as ethicalpaul suggests.
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