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# Boiler Sizing

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edited October 2017

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great article, now how do I size for a new boiler?
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You have to measure all the radiation and NOT the building.
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so how do I go about this? measuring all the radiation? the house is about 100 years old the boiler from 1986 approx. a burnham, no specs on it, we have three floors and a basement.
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Search around here for Radiator EDR calculations. You can also Google it. There are a few charts out there to help measure them.
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You have to identify the radiator type: height depth and number of colums per section. You then need to count the number of sections on each radiator. You can search this site for a listing of radiator types or look up "Boiler Data Book" which has radiators and boiler EDR information. How old is your existing boiler? What make and model?
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Bob
Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
Vaporstat with a 12oz cut-out and 4oz cut-in
3PSI gauge
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jayjayt said:

great article, now how do I size for a new boiler?

Check this out.. http://www.dunkirk.com/sites/default/files/Dunkirk Radiation Tables.pdf

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All you have to do is figure out the EDR of each radiator and then total them all up. Then you select the size of boiler by matching the total EDR of all the radiators to the Sq Ft of steam rating of the boiler. Don't bother with the BTU rating, just deal with the Sq Ft of steam.

Bob
Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
Vaporstat with a 12oz cut-out and 4oz cut-in
3PSI gauge
• Member Posts: 2,708
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JT,
this is a steam system,
not hot water,
correct?