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.

boiler sizing

2»

Comments

  • Control_Guy
    Control_Guy Member Posts: 1
    Where to find a mod/con boiler as small as 30,000btu?

    This looks like a good place to ask this question . . Does anyone know where one can find a 30,000btu (max) mod/con boiler. The smallest I have bean able find myself is a 50,000 btu output with a 5:1 turndown.

    Any help is appreciated.
  • SWEI
    SWEI Member Posts: 7,356
    Smallest I have seen here

    is the 37k Cadet http://www.cadetboiler.com/InstallersModelsSpecs
  • gennady
    gennady Member Posts: 839
    1.2

    I use 1.15 pick up factor for hydronic systems.. Why 1.2?
    Gennady Tsakh
    Absolute Mechanical Co. Inc.
  • gennady
    gennady Member Posts: 839
    Ibr doe

    IBR = amount of heat radiators get from boiler. DOE =amount of heat IBR + heat loss in the transmission of heat from boiler to emitters. If piping is in conditioned space then it accounts as emitters, if in unconditioned space then it cannot be used as heat emitters and not counted as hear emitter. But when boiler starts from cold condition on design day temperature, then all mistakes in heat loss will show up. And when I see old gravity systems with 3" piping I m sure want to take this piping into account.
    Gennady Tsakh
    Absolute Mechanical Co. Inc.
  • Jean-David Beyer
    Jean-David Beyer Member Posts: 2,666
    heat loss number is the outside temperature.

    "What changes the heat loss number is the outside temperature"



    True as far as it goes. Actually the difference between the (desired) inside temperature and the outside temperature. And the thermal resistance of the building's envelope including infiltration leaks..
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,577
    previous gas consumption

    would an analysis of old gas consumption records be of benfit in refining a heat-loss calculation? obviously, the records would have to come from a couple of colder months with actual readings.

    in the case i am thinking about, there is no hot water-only hot-water heating--nbc
  • tom3holer
    tom3holer Member Posts: 45
    "Fuel Used" heatloss calc

    Nick,

    Absolutely a fuel used method is going to be a great backup and most likely more accurate.

    Here is a link to  a very helpfull way to do a fuel used method using your gas.



     bills.http://www.terrylove.com/forums/showthread.php?50715-Newbie-with-Alpine-issues/page2



    Be sure to do it over several colder months. Thes results should come out almost the same.



    Tom
This discussion has been closed.

Categories