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Gravity system

I need to replace a 104 year old gravity boiler in a 2 story house with a demand of 72k demand acording to the radiator sizes. The system is split with 2 3" supplies and 2 3" returns for close piping. I can not find any boilers with that size and amount of tappings. The Utica boiler has 2 2" supply tappings and one return. Can I use this configuration and tee the return and still have enough flow? Circulators are unfortunately not an option.


  • Ryan

    circs not an option?, ever considered this? , it may have the tapping sizes you`re looking for.
    Always try not to use a standing count though, HL calc is the best method.

  • scrook_2
    scrook_2 Member Posts: 610
    boiler sizing

    Use total radiation (radiator size/count) for steam, but use structure heat loss for hot water systems.

    Why isn't a circulator an option?
  • Al Roethlisberger
    Al Roethlisberger Member Posts: 194
    My overhead gravity system was converted

    Not a pro here, but my old overhead gravity system uses a 6 inch(I think) riser and return, but were reduced to 1.5" to connect to the boiler and circulator sometime around 1991.

    And this reduction was original to the system.

    Since I assume you would be converting to a closed circulated system, why can't you use circulators since convection isn't going to be the vehicle anymore?

    More than anything else, I am just curious what the barrier is for this application.


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  • Al & scrook,

    maybe he`s Amish?, just a thought, but could be?

  • Al Corelli_2
    Al Corelli_2 Member Posts: 395

    The Weil McLain EG series is a good choice here.

    It is the ONLY WM boiler I will install.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

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This discussion has been closed.