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Boiler sizing

mtlight Member Posts: 28
Prior to Hurriacane Sandy, I owned a Williamson GSA125. It produces 325Sq ft of steam. My connected load is 280 sq ft. This was very slightly oversized but seemed to work well. After the storm with boilers in demand I had to accept a Williamson GSA150. This provides about 380sq ft of steam and it oversized and shuts off on pressure a little to often and more hissing vents than before. My cutout is about 2 and cut in is .5. Okay here is my question. From viewing the specs of both of these boilers, they appear identical. The weight is the same, the dimensions the same, the sections the same, the tappings the same, all controls the same. the one difference appears to be the burner tray. The burner tray has 6 burners on the gsa150 and 5 burners in the gsa 125. It appears to me that smaller burner tray is what seperates the two size boilers. If i remover the larger tray and put in the 5 bburner tray, will i be converting the gas 150 into a gsa 125 which more fits my needs? It appears to be the only difference and maybe a draft hood size also. Both of these changes are easy to do without much cost . Please comment and let me know what you think. Thanks in advance


  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    I believe Chris did that with his Peerless, which had the same sort of design, and he had great success. Maybe he will chime in, if he is not too busy working on his ancient Refigerator.—NBC
  • KC_Jones
    KC_Jones Member Posts: 5,691
    That is a re-badged Weil Mclain and yes the only differences between the 150 and the 125 is the burner tray AND the draft hood. @ChrisJ made this change on his.

    I wouldn't hesitate to make the change if I was you. I have a system with 265 EDR and running the smaller version and it runs fantastic on my system, never short cycles.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • mtlight
    mtlight Member Posts: 28
    Ok. Thanks Gents. I’ll do this in the spring after the heating season in case any problems. I do see the regulator needs to be taken off the tray and moved to the new one. Nbd there.