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Best Condesing Boiler

HydroMan Member Posts: 14
I'm looking at a few high efficiency mod-con boilers for commercial application. I need between 1,000MBH and 2,000MBH, and would like to pipe variable-primary instead of primary/secondary. Any thoughts or recommendations on which boilers, maybe even a Top 3, you would choose?


  • CMadatMe
    CMadatMe Member Posts: 3,085
    Alot of Variables

    That's a pretty umbrella question your asking. My first look would be at the Viessmann Vitodens 200 on a rack system or a Vitocrossal. But reality might send me elsewhere. If money is no object then the Vitocrossal with a Weishaupt burner is the best in my opinion hands down. 98% AFUE in a single boiler that would easily do your 2mil. If redundancy then 2 smaller ones.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • SpeyFitter
    SpeyFitter Member Posts: 422

    I'd have a look at a Cleaver-Brooks Clearfire Condensing Boiler (Model CFC). This boiler has a 316 Titanium Stabilized downfiring fire tube heat exchanger for a lower head loss than many competing models (aka less pump power required).  Their boilers have a 5 to 1 turn down if I'm not mistaken, and they have 500 MBH, 750 MBH, 1000 MBH, 1500 MBH, 1800 MBH and 2500 MBH models.  If I were you, I'd consider redundancy by picking 2 or 3 smaller boilers instead of 1 larger boiler. This will give you a higher turn down ratio by teaming up the boilers to act as one, and if one should fail, you have some heat at the very least due to the redundancy.
    Class 'A' Gas Fitter - Certified Hydronic Systems Designer - Journeyman Plumber
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