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Radiator clanking

Timco Member Posts: 3,040
be sure both valves are fully open.

Just a guy running some pipes.


  • Matt_55
    Matt_55 Member Posts: 1
    radiator making noise

    Hi. I have a problem with my radiator. I live on a second floor of a 3 floor apartment. My radiator makes loud noises. It sounds like clanking or someone is hitting a hammer against it. I have no problem with the whole radiator heating up. Its steam heat. I think that the banging is coming from air in the pipes. This would mean that I would have to bleed it. I look on the internet and I found out how to do that but my radiator does not have the valve that can help bleed it. I looked all around it and i could not find it. Is there anything that you recommend? Do you think that it is air in the pipes? I have attached two pictures of my radiator to show you. Hope they can help with the situation. Thanks I really appreciate it.
  • coalcracker
    coalcracker Member Posts: 51

    The return pipes might not be draining back into the boiler because of settling of the floors, etc. They must be pitched to return by gravity. Also, the boiler water could be dirty and producing "wet steam". Both are mechanical problems and probably out of your control.
  • Timco
    Timco Member Posts: 3,040

    You have steam, and only hot water systems get bled. The vent on the rad lets the air out as steam fills the rad. The banging is steam passing condensate (water) in the same return pipe. As the previous post said, likely pipes not allowing condensate to run to boiler. May also be a bad valve on the rad.

    Just a guy running some pipes.
  • Scott Larabee
    Scott Larabee Member Posts: 28

    Am I just tired, or is that steam vent upside down!

    Turn the vent 180*.


  • bob young
    bob young Member Posts: 2,177

  • James Crosby_2
    James Crosby_2 Member Posts: 6
    Damm good call

    That steam vent is indeed upside down, and to think I studied those pictures for some time and never noticed, cool
  • Good catch, guys

    but re-read the original post: He says the rads heat up all the way. So either those vents are leaking, or the system pressure is way too high.

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  • kpc
    kpc Member Posts: 2
    riddle me this....

    if it has two pipes,and its steam...should that air vent even be on there?is a steam trap broken or missing?
  • steven E.HEAT
    steven E.HEAT Member Posts: 47

    it must have a wet return.trap only if dry return.
  • It's a 2-pipe, air-vent system

    which does not vent air thru the returns, so rad vents are needed. This was the precursor to Vapor.

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  • ttekushan_3
    ttekushan_3 Member Posts: 958
    Optical illusion?

    No answers from me today. Frank, I only have observations/questions on this steam variant that could shed light on the problem.

    Following the right edge of the radiator down and comparing it to lines in the paneling behind it, is it possible that the radiator is pitched towards the supply line on the right rather than the return on the left (the vent side)?

    Shouldn't the radiator pitch towards the return in the two pipe with air vent system? Especially since it appears that the return is smaller than the supply and that the bushing is not eccentric.

    I suppose also that both valves must be in the fully open position.

    Interesting thing about that vent upside-downism. Isn't it possible that this radiator could eventually heat if vented by another radiator on the same lines (with the returns joined above the wet return line) which has its supply valve closed but the return valve open? And the corollary: wouldn't that other radiator on the same line heat with its supply valve closed by getting the "back steam" from this radiator (and thereby confounding a tenant elsewhere who is getting heat from a "closed" radiator)?

    Are these issues why they stopped doing this? I'm just getting a funny picture in my mind where individual tenants are simultaneously standing in their respective kitchens staring at their respective kitchen radiators, each unaware of their counterparts standing there regarding their radiators with the same confusion. One or another of the unwitting participants diddles with a valve and everything nonsensically changes all by itself!

This discussion has been closed.