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Radiator leaking at bottom - rusted??

mookie3333 Member Posts: 83
edited October 2017 in Strictly Steam
I have a radiator that was sitting unused for a couple years. I just installed it to heat an extension in the back of my house. Heats well, but I noticed water dripping from the bottom of 2 of the sections. Anyone experience this before? Is it rusting through? Should I look into a new radiator? Or can this be fixed? Thanks guys.


  • Ironman
    Ironman Member Posts: 7,342
    edited October 2017
    It's probably leaking at the push nipples. Practically speaking, it's time to scrap it. SOMETIMES, you can disassemble it and replace the push nipples if their sockets aren't deteriorated, but it's a lot of work and a low percentage success rate.

    If you get a used rad to replace it, you need to pressure test it before using it so that you know it's good to go.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • flat_twin
    flat_twin Member Posts: 350
    I read long radiators can leak if they're lifted without enough support and are allowed to flex a little.
    We shortened a very long radiator for a room remodel a few years ago. I made some long wooden wedges and carefully split the radiator sections. We smoothed the mating surfaces, put some gray pipe dope on the push nipples, gently tapped it together and replaced the threaded rods. Just snug, not too tight. Got lucky and no leaks.
  • Jamie Hall
    Jamie Hall Member Posts: 22,899
    Probably the push nipples are rotted out. They do. However, do not despair. I have had very good luck indeed with the following procedure. Disassemble the radiator at those two leaking points. Do this very carefully so as not to strain anything. Take the old push nipples out (somewhere there is a firm which can machine new ones, by the way). Then I reinsert them rotate 180 degrees up, so the bad spot is up. Cleaning everything, of course. Then, if you look carefully, you will note that while the push nipples are supposed to be the seal, the radiator sections actually come very very close together when the thing is assembled. Place a ring of red sealant -- such as you might use for an engine -- around that area so it will be squeezed when you pull the thing back together. The reassemble the radiator. It is MUCH better to use long pipe clamps to pull it together evenly rather than depending on the tension rods or pounding on it. You should be good to go.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • mookie3333
    mookie3333 Member Posts: 83
    Wow! Didn't even know you could take these radiators apart. What's the advantage to taking it apart and trying to replace the push nipples, rather than just scrapping it and getting one of the new grey OCS radiators? Sure it might cost a couple bucks more, but is there any advantage of the old radiator over a new one?
  • Fred
    Fred Member Posts: 8,542
    Yes, they can be taken apart. In reality there are advantages to finding a good used or new radiator. The cost may be the only disadvantage. If you replace it, it probably makes sense to do a heat loss for the room you are installing it in and buy one properly sized for that room. I'm sure you used this one because you happen to have it and it may be too big or too small. If you buy new, you may have to skim your boiler a week or two after installation. There will be some oils in the new cast iron radiator that will make its way back to the boiler.
  • mookie3333
    mookie3333 Member Posts: 83
    Fred - yes you're completely correct. I just happened to have this laying around my house unused. Will size the replacement one accordingly. Apparently, it has stopped dripping for the time being. Will monitor it, and if it gets worse, I'll replace. Thanks guys.
    EBEBRATT-Ed Member Posts: 15,304
    After it heats up it may seal itself. just keep an eye on it