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Anyone know the EDR for this antique radiator?

Ed59 Member Posts: 13
Does anyone know the EDR for this antique?

It varies from about 4-3/4" to 6" in width, height is 39". The end sections are kind of flat, internally they're more like columns but just an indentation on the face, not a hole that goes all the way through.

We just got an estimate for boiler replacement, but the contractor did not do an EDR calculation. Didn't even look at most of the radiators. Now after reading this site and starting the books, I'm wondering if the size is right, so trying to figure it out myself.


(not sure why the forum always wants to rotate my photos that are taller than wide)


  • BobC
    BobC Member Posts: 5,477
    This is just an approximation

    The EDR is determined by the surface area of the radiator so if you take a piece of string and put it around a column at a few different points and measure the circumference and then average those circumferences you will have an average of the columns circumference over it's length.

    You said it's 39" high so lets subtract 4" from that; that gets us 35" so multiply that by the average circumference and that will tell you how many sq inches each column has. Dived that number by 144 to find out how many sq ft each column is and multiply that by the number of columns to get the EDR for that radiator.

    That will get you pretty close to the EDR of that radiator, it's not perfect but should be good enough.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • rrwitherspoon
    rrwitherspoon Member Posts: 104
    OMG What a beauty!!!
  • Fred
    Fred Member Posts: 8,542
    It looks like it is pressed steel. Is it steel or cast iron?
  • JStar
    JStar Member Posts: 2,752
    Looks like an American Radiator Italian Flue radiator, or some type of flue-radiator.
  • JimP
    JimP Member Posts: 87
    This radiator was originally rated at 7 square feet per section by the manufacturer.
  • Steamhead
    Steamhead Member Posts: 16,832
    Closer to the Verona, not the Italian Flue.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • Jason_13
    Jason_13 Member Posts: 304
    I am assuming this is a steam boiler and not a hot water boiler.
  • SethK
    SethK Member Posts: 43
    It's a Carron Antoinette, 4443 BTU for ten sections at 60 Celsius according to one page, so 444.3/90 = 4.94 EDR if my math is right.
  • Steamhead
    Steamhead Member Posts: 16,832
    Where'd you find it? Can you post a link?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • jbmoff
    jbmoff Member Posts: 76
    I recall seeing many of those in the Victorian homes in Cape May NJ and a few brownstones back in my old neighborhood of Hoboken. Those unique babies would stop people DEAD in their tracks....
  • SethK
    SethK Member Posts: 43
    I think I found it by looking at google images of ornate radiators. Here's where I got the specs:


    However these seem to be newly made, I am assuming they have the same specs as the antiques.