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Oversized boiler

TonyS Member Posts: 849
I went to look at a job that was put in a few years ago, its got everything, cast rads in the old section, baseboard fin and radiant in the new. Complete disaster!

The boiler was installed a few years ago also, Burnham cast iron 170k ,its about a 100k over sized. Question is ...How do you guys feel about removing burners to down fire this beast. PROS...CONS AND TECHNIQUES ?


  • Ironman
    Ironman Member Posts: 7,350
    I Wouldn't Do It


    I wouldn't do it under any circumstance. If you do, you own it and all the ramifications that come with it. It's illegal to modify the gas train in a manner not approved by the manufacturer and AGA. I'm sure Tim can give better specifics.

    I'd look at a buffer tank or a properly sized boiler.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Tim McElwain
    Tim McElwain Member Posts: 4,608
    Not a good idea for a couple of reasons

    1. The overall efficiency will be affected as you still have to heat all the sections

    2. Safe ignition can also be a problem depending on what burners are blocked off.

    3. It could affect the warranty on the boiler if that is still a factor depending on age

    4. Manufacturers of equipment will not authorize such a move.

    You can by changing all the orifices to smaller size or adjusting pressure typically reduce input about 10% which is not the best but better than blocking off burners.

    In all cases I would do a before and after combustion analysis.