can I cap off a hot water radiator?

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by pronouncedeyen, Oct 1, 2009.

  1. pronouncedeyen

    pronouncedeyen New Member

    Messages:
    46
    Location:
    Baltimore, MD
    At the beginning of our bathroom remodel we removed the hot water radiator so we could redo the floor. Well everything under the floor was a disaster so we haven't put it back yet. And now it's getting cold.

    Does anyone sell a cap for the iron pipe that's the size of a standard female residential radiator fitting? If I could cap it off I could turn the heat on.

    Otherwise it's going to be a mighty cold fall/winter.
  2. SewerRatz

    SewerRatz Illinois Licensed Plumber

    Messages:
    1,705
    Location:
    Chicago, IL
    Did your radiator have one or two pipes? If it is a two pipe system, I would think twice about capping it off. It all depends on how it is piped. If they put the radiators in a series loop, you would stop the rest of the system from getting hot water. Now if they plumbed them in a parallel type as pictured in the bottom part of the picture you might be able to get away with it. But there is a chance of causing an unbalanced load.

    Attached Files:

    • ch.jpg
      ch.jpg
      File size:
      17.3 KB
      Views:
      1,229
  3. pronouncedeyen

    pronouncedeyen New Member

    Messages:
    46
    Location:
    Baltimore, MD
    SewerRatz: It's the second kind. Two pipes to each radiator that go all the way to the big supply & return pipes in the basement. Nothing is connected in series like the first diagram.

    The problem I have is that the system is almost 100 hundred years old. I don't want to try and pull off the piece that connects to the radiator to get down to a standard iron thread to cap it off because I'm worried about things breaking apart. Do 100-year-old hot water radiators use a standard thread? Can I get a cap made out of that thread?

    If not, is there some way to cap off the pipes without removing pieces to get to a standard iron pipe thread?
  4. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,835
    Location:
    Cave Creek, Arizona
    radiators

    Few, if any, "radiator" systems are looped. The valve and elbow threads at each end are "proprietary" and are not even interchangeable between brands, so there are NO caps that will fit them. You have to remove the valve and elbow in order to cap the pipes. Hot water components will unscrew fairly easily. Steam could be almost impossible to remove.
  5. frenchie

    frenchie Jack of all trades

    I'm used to steam pipes, so this may be overkill... but...

    If it's really stubborn...

    grab a 3 or 4 foot length of 1-1/4" or 1-1/2" (whichever size best fits over the handle of your pipe wrench) steel pipe - and use it to give yourself a longer handle. The extra leverage makes a huge difference.
  6. nhmaster

    nhmaster Master Plumber

    Messages:
    3,189
    Location:
    S. Maine
    You are kidding right? :confused:
  7. nhmaster

    nhmaster Master Plumber

    Messages:
    3,189
    Location:
    S. Maine
    You are joking right? Or have you not seen the damage and injury that can result in doing just such a thing? Pipe wrenches are sized the way they are for a reason. Never put a cheater bar on a pipe wrench. Get a bigger wrench.
Similar Threads: water radiator
Forum Title Date
Plumbing Forum, Professional & DIY Advice Water pressure,water hammer and hot water radiators Feb 5, 2014
Plumbing Forum, Professional & DIY Advice Advice on steam radiator air vent leaking water Jan 27, 2014
Plumbing Forum, Professional & DIY Advice 2 zone, hot water upstairs, steam radiators downstairs Oct 29, 2013
Plumbing Forum, Professional & DIY Advice Converted Hot Water System Column Radiator removal Jul 16, 2013
Plumbing Forum, Professional & DIY Advice Help! CI Hot Water Radiator sits higher than the unions. Oct 27, 2010

Share This Page