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Correct size & Brand Boiler

sioux Member Posts: 4
I need to replace my old gas boiler. I live in Massachusetts. I have gotten some quotes. The 3 brands suggested are Viessmann, Lochinvar and Weil-McClain. Only one company has done a heat loss calculation. I have ‘a lot’ of windows. It has always been a room that is hard to heat. I want to get the correct size boiler. Any suggestions would be much appreciated.



  • Jamie Hall
    Jamie Hall Member Posts: 17,165
    You absolutely have to have a heat loss calculation. Trying to size or replace a boiler without one is just a guess.

    Further, it is best to do a room by room heat loss calculation. That way, if there is a space which is harder to heat, a good contractor can figure out how to get more heat to it (there are lots of options for that).

    All three boiler brands are fine. It's all about the installation. A good installation will make any of them work well. A poor or cheap installation and none of them will.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • JohnNY
    JohnNY Member Posts: 2,762
    A modulating boiler will fire to the heat loss of the building envelope.
    Contact John "JohnNY" Cataneo, Master Plumber
    in New York
    in New Jersey
    for Consulting Work
    or take his class.