Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.
If our community has helped you, please consider making a contribution to support this website. Thanks!

Sizing a replacement steam boiler

Lomer
Lomer Member Posts: 1
in THE MAIN WALL

I presently have a Peerless 200,000 btu natural gas steam boiler that will have to be replaced soon. The cast iron is cracked and leaking steam. I measured all of the radiators in the house and determined that I have 305 square feet of radiation. The house is 2250 square feet on three floors. This is an attached row house in Brooklyn NY with insulation in the roof and replaced windows. A plumber who came and looked at it suggested replacing with a Burnham 175 mbtu unit. But based on the square footage of radiation that seems oversized. The pipes in the basement will be insulated. Is this the right calculation; 305 x 240 x1.33 = 97,356 btu ?

Even if I think the heat loss of the house is on the high side at 60 btu per square foot that is;

60 x 2250 = 135,000 btu

Comments

  • ethicalpaul
    ethicalpaul Member Posts: 7,855

    Forget all those other facts. All that matters is the EDR vs the sq. feet of steam. The Peerless 63-03 is the right size for you.

    image.png

    NJ Steam Homeowner.
    Free NJ and remote steam advice: https://heatinghelp.com/find-a-contractor/detail/new-jersey-steam-help/
    See my sight glass boiler videos: https://bit.ly/3sZW1el

    mattmia2STEAM DOCTOR
  • STEAM DOCTOR
    STEAM DOCTOR Member Posts: 2,435

    Assuming that your numbers are correct, then I would sadly have to report, that the plumber is more cracked than the boiler block.

  • STEAM DOCTOR
    STEAM DOCTOR Member Posts: 2,435

    If the plumber did not determine the heat output of the radiators, then he is a ranked amateur at best.

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 18,807

    If you have 305 sq ft of radiation that is all you need to know. Forget about BTUs. The boiler rating plate or spec sheet will show how many sq feet the boiler is rated for you don't need to do any conversions or add the pickup factor that is already done by the boiler mfg.

    But your calculation of 305 x 240 x 1.33 is correct.

    But just use the sq ft rating it is easier.

    For Burnham the Steam Max STMX125 is 125,000 input will do 321 square feet of steam. They also have the Independence, but I would stay away from that one.

    I am not a Burnham fan however, but the steam max is supposed to be a good boiler

    Single most important thing is to INSIST the installer follows the boiler mFG piping diagram. Don't assume he knows this. You will hear "I have been doing this for 20, 30, 40 years yada yada.

    Be careful we get horror stories on here weekly that need to be re installed.

    And make sure they install a skim tapping and skim the boiler if needed.

    You mentioned Brooklyn so maybe @JohnNY , @EzzyT or @Mad Dog_2 . I don't know if they all work in your area.

    mattmia2ethicalpaul

Categories