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Radiator Sizing

I have a radiator I’m trying to calculate the EDR for and I’m coming up with nothing. Can some one point me in the right direction?

Comments

  • Nate0846
    Nate0846 Member Posts: 7
    I think found a match. If I use the old column style and call it 5 columns and use the 14” height and 12 1/2” width it comes up with a 4. So I will multiply that by the sections and hope it comes out correct. This is a water boiler that I think was converted from steam.
  • random12345
    random12345 Member Posts: 469
    I wouldn't do that. Inaccurate. Instead do you see any embossed writing on it anywhere? If you can provide a manufacturer name, I might be able to help. Sometimes you'll find that around the tapping where the valve is attached in that picture or on the other side. It might also be on the columns of the first or last sections. This looks similar to a Zenith made by American Radiator, but it's not quite the same. When was your house built? Do you believe that rad is original to the house?
    Ucuellar2011
  • Nate0846
    Nate0846 Member Posts: 7
    No embossed writing on it that I could see. The house was built 1900 and yes it appears to be original to the home.
  • random12345
    random12345 Member Posts: 469
    edited October 2022
    I would take a second look with a flashlight. Look all around. Maybe you'll luck out. I couldn't find anything. Maybe it's in Dan Holohan's EDR book? If I had to guess, I would say it's between 3-4 sq ft/section, but those are steam ratings. You then need to convert to forced hot water ratings, in which case, the right way to size the boiler, if that's what you're trying to do is to perform a Manual J calculation for your house. Or is this for some other reason?
  • Nate0846
    Nate0846 Member Posts: 7
    It’s for a client I’m working on to quote a new boiler. I’ve looked throughly for any markings and couldn’t see anything. 😔
  • random12345
    random12345 Member Posts: 469
    edited October 2022
    I'm not a pro by the way. Just like digging up info online. Aetna Flue Window Radiator, made by American Radiator Company. You were spot on. 4 sq ft/section.

    https://babel.hathitrust.org/cgi/pt?id=uc2.ark:/13960/t83j3bp53&view=1up&seq=85&q1=aetna

    56 total.

    At the risk of telling you something you already know...Since it's painted bronze, the effective EDR will likely be 10-20% less. Not sure if you're installing a steam or hot water boiler...

    https://heatinghelp.com/heating-museum/does-the-color-of-a-radiator-matter/
    Erin Holohan HaskellNate0846
  • KC_Jones
    KC_Jones Member Posts: 5,722
    Nate0846 said:

    It’s for a client I’m working on to quote a new boiler. I’ve looked throughly for any markings and couldn’t see anything. 😔

    Are you sizing the water boiler from the system EDR?
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • Erin Holohan Haskell
    Erin Holohan Haskell Member, Moderator, Administrator Posts: 2,276
    @Nate0846, that looks like the American Radiator Company's Aetna Flue Window Radiator seen here in The Ideal Fitter (1911):


    President
    HeatingHelp.com
    Nate0846
  • Erin Holohan Haskell
    Erin Holohan Haskell Member, Moderator, Administrator Posts: 2,276
    Sorry @random12345. I missed your comment about about the Aetna above. I guess I was too excited to visit our library. :D
    President
    HeatingHelp.com
    Nate0846
  • random12345
    random12345 Member Posts: 469
    I understand where you're coming from. :)
    Erin Holohan Haskell
  • Nate0846
    Nate0846 Member Posts: 7
    @ramdom12345 Thank you! Pro or not I greatly appreciate you digging that up for me! I’m glad I was accidentally on track when calculating it. 👍🏻

    To be honest I did not know that the paint affected the the EDR. 😳
    I’ve been getting more boiler quotes due to one of our designers retiring so I’m seeing more than I used to. Thank you for the link! 

    @KC_Jones this is for a water boiler and I’m taking the radiators in to account and the load for the house for a comparison. 

    @Erin Holohan Haskell thank you so much for digging that up for me! I will be buying that book and keeping with me!

    I greatly appreciate all of your help everyone! 🙌🏻
    Erin Holohan Haskell