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Mascot FT Wall-Mount Combi Boiler 199 MBH w/pump

dzlfarmboydzlfarmboy Member, Email Confirmation Posts: 1
edited January 11 in THE MAIN WALL
Hi all, New here and getting ready to build a Post frame home with 2880sqft of living space and a 4000sqft of shop/garage/hobby room. I am going to be doing radiant floor heating in all of it and was curious on what would be a suited boiler for the job. I was quoted this Combi unit for my kit but uncertain If I should even go combination or separate units if they operate on different efficiency methods. Any input would be great and thoughts on this recommended boiler. Thanks


  • Jamie HallJamie Hall Member Posts: 14,793
    Stop! Your first step is going to be to figure out how much heat you actually need. The full Manual J calculation can look a bit daunting, but Slant/Fin has a very easy to use -- and quite accurate calculator here: which will give you room by room heating loads, as well as the total heating load.

    Then you can plan two things: first, whether your radiant floors can manage the whole load (probably) and at what temperature they will need to run to do it, whether you need some additional heat in some areas, and whether you need additional, faster responding heat in some areas (perhaps the shop/hobby/garage might not be used all the time, but need to be warmed up for a project, for instance).

    Further, you can figure out what size boiler you actually need for the heating.

    You can also sit down and figure out what you really need for domestic hot water.

    Now you will be in a position to evaluate the Mascot -- and other possibilities. With the heating boiler, it is important that it match the actual load, and be able to modulate down far enough to continue to do so, even in warmer weather. With the domestic hot water, obviously it is necessary that it have the capacity to handle you hot water needs.

    Sometimes these two goals can be met in one unit, but very often, for maximum efficiency, the heating boiler needs to be smaller -- sometimes a lot smaller -- than the tankless domestic hot water heater. In your situation that may not be the case; you are heating a lot of area, and may need more capacity on the heating side -- but you simply can't tell until you get that first step done.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.
    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • IronmanIronman Member Posts: 6,142
    I completely agree with Jamie. The heat loss calc is the first step and the FOUNDATION for designing EVERYTHING. There's' no "one size fits all". Don't let some internet peddler convince you otherwise.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 7,994
    The above comments are excellent and in addition to that if you use radiant in the garage, workshop etc when it's cold out you need to leave it running all the time if you wnat heat. Radiant systems come up to temp slowly so you can't turn them off or down and no night setbacks
  • BillyOBillyO Member Posts: 245
    Laars mascot a good unit with great support

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