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cast iron radiators

sean_20 Member Posts: 1
Is there a way to determine the btu output on older cast iron radiators? thanksfor any info.


  • Brad White_9
    Brad White_9 Member Posts: 2,440

    First place I would stop is the Burnham.com Web Site. They have tables as part of their "Heating Helper" document. About a hundred pages chock full of neat stuff, radiator outputs among them. Their product brochure on radiators also has some additional and overlapping data.

    Next, if your types are not found, Dan's "EDR" book is an excellent reference.

    Keep in mind all that you seek will give you "EDR" or "Equivalent Direct Radiation". That is essentially the outer surface volume of the radiator including nooks and crannies, expressed in Square Feet.

    They are not in themselves a BTU output value. These translate into heat output on a proportional scale relative to radiator temperature and room temperature.

    With 215 degree steam this is 240 BTU's per EDR in a 70 degree room. With 170 degree average water temperature this drops to 150 BTU's per hour per SF EDR and drops from there as the water temperature drops.

    Hope this helps!


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