Click here to Find a Contractor in your area.
Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit

Bleeding Old Baseboard Like Radiaotors

nis2008nis2008 Member Posts: 7
Does anyone know what’s the official name of this type of radiator? Also, any idea where I can find the bleed valve? I have looked all all of the radiators and I don’t see anything except the bottom bolt piece but I’m not sure if that’s a bleed valve (doesn’t appear to be so). Thank you for your help.


  • Jamie HallJamie Hall Member Posts: 14,835
    Since I see a steam vent in one of the pictures, they are set up for steam -- and one doesn't bleed steam.

    They are finned convectors, for use on one pipe steam systems.
    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
  • JUGHNEJUGHNE Member Posts: 7,867
    Those look to be 1 pipe steam convectors......not hot water.

    The round devices you have sticking up are air vents which should automatically remove air and then close when the steam gets there.
    One does not manually bleed air from steam systems.

    What problems are you having with the heating system?
  • dopey27177dopey27177 Member Posts: 433
    These are fin tubed convectors.
    There are two types.
    yours are 3 tubed finvectors.

    The other is one steel pipe with fins on them.

  • nis2008nis2008 Member Posts: 7
    Thank you all for the clarification. The round air vents do release a little air and then then piping gets hot. I hear loud banging in my pipes often and hence my thinking to bleed the radiators. But now I understand why that wouldn’t apply.

    I would say that I had issues with my low water cut off a few months ago and the boiler didn’t stop adding water to the boiler, which ultimately caused the round air vents to spurt water out of them. I had the Low water cut off replaced and it works fine now, however, I have never replaced the round air vents. Do you think they were ruined by the water spitting out of them initially?

    Also, what kind of maintenance do you recommend for these steam radiators other than vacuuming the dust out of the fins?
  • JUGHNEJUGHNE Member Posts: 7,867
    Flooding with water like that can ruin the vents, but if they are working now and not passing water or steam they should be fine. If they stick shut then the air can not leave the convector and you get no heat in that one.

    One cause of the hammer could be the slope of these convector elements (the fin tube part). The should be sloped to drain towards the big valve on one end, that is to drain away from the vent end. The slope should be noticeable by looking at it.
  • nis2008nis2008 Member Posts: 7
    That makes sense. The vents are working but do have a hissing sound. Would you recommend replacing them if there is a hissing sound (in terms of loss of heat or performance)?

    Also, what angle do you recommend to tilt the fans? Slightly or noticeably?

  • mattmia2mattmia2 Member Posts: 2,297
    the valve also needs to be all the way open or closed, a partially closed valve will trap water in the convector.

    does the vent hiss after it gets hot?

    what pressure is the pressuretrol on the boiler set at? Are there vents on the steam mains themselves and do they open when cold?
  • nis2008nis2008 Member Posts: 7
    Apologize for the delayed response. The pressure on the boiler pressuretrol is set to 10PSI. The vent hisses right before the convector gets hot and stops afterwards. I’m not sure where to look to answer if there are vents on the steam mains. There is the steam equalizer and there is a vent grill on the front cover.
  • Jamie HallJamie Hall Member Posts: 14,835
    10 psi? are you sure? Please take a photo of the control and post it, if you can. That's WAY too high. If that's what you are running at, it's no wonder you are having problems -- the vents won't work properly above 3 psi, and may not even survive at 10 psi.
    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
  • nis2008nis2008 Member Posts: 7
    edited February 2020
    Please see attached photo. It’s a 3 story house (counting the basement which is at ground level).
  • mattmia2mattmia2 Member Posts: 2,297
    given the manual reset button i believe that is a safety control, not the operating control, there should be another pressuretrol or vaporststat somewhere. it should be set to more like 1psi, but you have to be careful the linkage doesn't fall apart if you go below the lowest marking.
  • nis2008nis2008 Member Posts: 7
    edited February 2020
    Thank you again. I have found the correct one and it’s just like you said. See photo.

    Your responses have been very helpful for me.

    Two questions -

    1. can you please explain how these convectors work end to end? I understand the water is boiled in the boiler and I think steam rises through the pipes to the connectors. But also I have to drain the boiler once a week to blow out any gunk so that the low water cut off doesn’t get stuck. But I’m curious on where is the dirt coming from?

    2. Is this convector system considered old? Would you recommend replacing it for future home value? If yes, what are the options to replace it without ripping out all the walls and plumbing?
  • SuperTechSuperTech Member Posts: 1,538
    Never replace the original convectors or radiators in an old house! It's the worst thing you can do, you will lower the value of the home! The only reason that houses are no longer built with cast iron radiators, convectors and boilers is because it's easier and cheaper to install forced air.
  • nis2008nis2008 Member Posts: 7
    Understood! Thank you so much for all of your support!

Leave a Comment

BoldItalicStrikethroughOrdered listUnordered list
Align leftAlign centerAlign rightToggle HTML viewToggle full pageToggle lights
Drop image/file


It looks like you're new here. If you want to get involved, click one of these buttons!