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steam boiler replacement

Matt_21 Member Posts: 140


  • Matt_21
    Matt_21 Member Posts: 140
    i have to replace an existing steam boiler

    can i replace it with the same size or should i add up all the radiators to figure the btu's? i know older hot water boilers are usually oversized and you should figure the actual btu loss to size the boiler but i wasnt sure if this applied to steam boilers if i add up the radiator areas, is there anything else i have to figure in to size the boiler?
  • Brad White_9
    Brad White_9 Member Posts: 2,440
    It is all in the radiation

    Figure out your connected square feet of radiation ("EDR" or Eqivalent Direct Radiation") and size your boiler to be close to but still exceed this number.

    Where building heat loss comes into play with a steam system is how your radiators (the EDR again) are sized in the first place. Unless you are planning on removing radiators, use the connected radiation to size the boilers. If you use the I=B=R capacity, that has a 33% (1.33 multiplier) factor built in. If your mains are insulated and piping is limited, this may help you if your boiler size to radiation size is close to the margin.
  • everything

    Everything what Brad said is correct... Do you have any specfiec brand boiler? No matter what brand, the new boiler will be junk if its piped in wrong... Make sure you get a true boiler company to do the job...
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