Heating Help

CI Radatiators

I'm a hot water guy with a steam boiler to replace. An old church (circa 1920s) with cast iron radiators - they will stay. I've been asked to survey the system and determine their (EDR) output.  The internet has been helpful - Columbia, Colonial, Utica Boilers radiation tables and a few others..
My questions - what is the difference between tubes and columns?
There are 11 radiators plus a exposed uninsulated piping, But I have one radiator a 7  tube or column with 20 sections, 49" long x 12" wide x 19" (not counting the 2" or 3" of support feet that I can not find a sizing table to determine its EDR. Seems like 6 tube/columns is the max. So how do I finds ists EDR?

CI Radiators

Hi- Look at the post below on Boiler Sizing. There is an chart attached to my answer that maybe of help to you.
- Rod

And

if you're not sure, post pics of the radiators here. We can tell you what they are.