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Combo Boiler

Hello All,

I have someone looking for a High efficiency heating boiler with a stand alone DHW heat exchanger in it (like and instaneous/on demand). I know someone out there has one but I don't know who. I would prefer to go with a Knight and a Indirect but they feel this circumstance requires this "Combo" boiler.



Anyone have any names?

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Comments

  • bob eck
    bob eck Member Posts: 930
    combo boiler

    check out triangle tube prestige excellence 95% AFUE gas boiler and indirect water heater all in one unit.

    110,000 btu boiler with 14 gallon stainless steel indirect water heater that delivers 180 GPH of domestic hot water.

    stainless steel heat exchanger + ss indirect water heater + vents with PVC pipe + wall hung boiler + 95% AFUE + outdoor reset control + domestic hot water priority

    great unit I have one in my house.

    email me if you want a price eckrobert@rcn.com
  • L'town Radiant_2
    L'town Radiant_2 Member Posts: 39
    Thanks Bob,

    that would be perfect but I shoould have mentioned that I need about 190,000 BTU/h output...

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  • 190K

    That's the heat load?  Big house.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • L'town Radiant_2
    L'town Radiant_2 Member Posts: 39
    Yep

    7,000 square feet!

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  • HDE_2
    HDE_2 Member Posts: 140
    Won't find one

    Most combi's tap out at 160,000 or less

    Navien may be the biggist when it arrives at 199,000 but with a 7,000 sq ft house I doubt any combi boiler can meet the DHW demand with gpm limitations ranging from 2 to 5 with a 70 degree rise.
  • Devan
    Devan Member Posts: 138
    7000 sq. ft house

    but what's the peak demand for hot water.



    At 7000 sq. ft, theres got to be at least one human car wash shower system and a large soaking tub.



    No on demand unit in my opinion.
  • SpeyFitter
    SpeyFitter Member Posts: 422
    RUN!

    Why do they insist on a Combi/combo unit?

    How many bathrooms/showers & appliances that require hot water?

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This discussion has been closed.