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Weil McLain cga 5

Snowmelt Member Posts: 1,295
I have a 3 year old cga that I am taking out of a customers house. Like I said irs only three years old, one of my friends wants it but it’s just a little bit oversized. What’s involved in reducing the gas input/ output? Is it as simple as blocking off a burner. Is that going to effect the flow size? Hypothetical the existing boiler is 102 output and I only need 75, how would you go about doing this?


  • kcopp
    kcopp Member Posts: 3,830
    You cant. And really should not. Boiler is designed to run w/ the orifices' provided. By you messing w/ that you could get sooting and excessive CO.

  • Snowmelt
    Snowmelt Member Posts: 1,295
    Ok thanks, what about lowering the W.C in the gas valve?
    HVACNUT Member Posts: 4,215
    Same. The boiler was tested at 3.5" manifold pressure with all the burners. You mess with it, it's on you.
  • The Steam Whisperer
    The Steam Whisperer Member Posts: 760
    edited July 2020
    If you're putting it in a high mass radiant floor or gravity conversion... the extra capacity really shouldn't be a problem. If you're running low mass, IE fin tube baseboard... then I might have a concern, especially if zoned.
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  • unclejohn
    unclejohn Member Posts: 1,751
    I would not even worry about the over size other than fuel cost. Can't tell you the number of times I have seen boilers way over sized. I have taken 250K out and put 140K in.