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Radiator heating backwards?

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What would cause a radiator to start getting hot in the bottom corner on the air vent side? Most of my other radiators seem to first get hot on top, and on the supply valve side. I changed air vent to a smaller size because the vent would get hot too, and I thought it was maybe closing, but I'm still having an issue (still starts to get hot from the air vent side first). Anyway...this radiator doesn't heat the room that well -- it's only warm afterwards. It's the last radiator on the run and 4 floors above the boiler, but there's only 2 radiators off that riser. Riser is 1" and gets hot pretty fast, but the radiator not so much.

Comments

  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,846
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    Are all your radiators the same type? Can you show us a picture of the problem child?
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,844
    edited December 2021
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    You may find your answer on page 12 of this text
    Click on this link
    http://media.blueridgecompany.com/documents/ZoningMadeEasy.pdf

    But the discussion of "Flow Control Valves" starts on page 9.

    It is a good text to help you understand the engineering of your system but in "NON-Engineering" terms.


    NEVERMIND


    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
  • Jamie Hall
    Jamie Hall Member Posts: 23,322
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    Ah... @EdTheHeaterMan , I think our OP has a one pipe steam system...

    And no, I have no idea why the radiator would do that.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    EdTheHeaterMan
  • MonasDad
    MonasDad Member Posts: 11
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    Not the greatest photo but it's in a tenant's Apt and can't get access right now. And yes, should have mentioned it's a one pipe system. I'm about 50/50 column and tube radiators in the building, a 19th century Brooklyn townhouse.
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,846
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    Is there by any chance a signpost up ahead…?
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
    delcrossvEdTheHeaterMan
  • delcrossv
    delcrossv Member Posts: 742
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    Only guess is vent is Way Too Big and the steam is just zipping across to the vent.

    ??? Cue Twilight Zone music...
    Trying to squeeze the best out of a Weil-McLain JB-5 running a 1912 1 pipe system.
  • mattmia2
    mattmia2 Member Posts: 9,662
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    Maybe it is holding water and it is full in such a way that it is blocking access to everything but the nipples across the bottom and the last section? Is the valve open all the way? Did some part of the valve come apart and partially block the inlet?
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,539
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    @MonasDad

    Someone must have worked on that system and messed it up.

    You not going to run 2 radiators on a 1" one pipe riser. That supply valve looks like 1 1/4 or 1 1/2"

    Can you take pics of the riser and where it's connected in the basement?
  • MonasDad
    MonasDad Member Posts: 11
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    Thanks for all the input. I measured and it's 1" -- photos attached of the connection to the mains and the riser in the hallway.

    Why wouldn't you put two rads on a 1" riser btw?

    Valve is all the way open and functioning as much as I can tell. I've got a Gorton #4 on it now and it's still heating backwards.

    Also I'm thinking since we had the floors refinished in that room it's possible the rad was higher up off the floor and since I have it angled towards the supply valve there may be a low spot.


  • mattmia2
    mattmia2 Member Posts: 9,662
    edited December 2021
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    Is that a Clow? Can you get some more pictures of the bottom and especially close up of both ends? that isn't just an ordinary radiator. The one on the floor below. Not the problem at hand but both very curious and maybe a clue about something that happened at some point.
  • MonasDad
    MonasDad Member Posts: 11
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    Not sure what a Clow is but here are some pics


    mattmia2luketheplumber
  • dopey27177
    dopey27177 Member Posts: 887
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    When a radiator is set up with an 1 1/4" connection it takes an 1 1/4" pipe to supply it.
    An 1 1/4" riser will supply about 88 edr, where the valve will allow 66 edr into the radiator.

    Just a guess the two radiators are rated about 4 edr per section, there is about 18 sections on both radiators so we hqave 18 times 4 edr for a total of 72 EDR.

    A 1" riser can only supply 44 edr and a 1" valve will allow 28 edr into the radaitor.

    Based on a guesstimate you need a 1 1/4" riser.

    Jake
    MonasDad
  • mattmia2
    mattmia2 Member Posts: 9,662
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  • MonasDad
    MonasDad Member Posts: 11
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    Thanks again for the insight and info. Never heard of gasteam radiators before…wonder how it got into my building!? 

    Interesting about the 1” riser. I have another 1” riser but no radiators attached. So maybe radiators were attached later. Both rads have 10 sections of six tubes about 25 inches tall — so 40 edr by my calculation. 
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,846
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    It's not a Clow, but it may have been a similar unit. American Gas Products was a division of American Radiator based in New York, and no relation to the Massachusetts company that supplies bottled gases today. Clow was a Chicago company.

    It looks like this one was just being used as a radiator, as there's no evidence of any gas plumbing. The extension on the supply suggests it replaced a conventional radiator.
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24