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Derating EG 35 to EG 30

Sean_15 Member Posts: 6

Thanks for your response. Sorry I posted under a pseudonym, derating is a touchy subject, and for good reason. I got some #s from WM, and it seems quite feasible (don't like to give figures here though). If I was oversized on the order of say, an EG45 vs. an EG30, I wouldn't even think about something like this, due to the difference in boiler heating surfaces, stack diameters, etc. Nor did I contemplate plugging a burner orifice, as uneven heating would invite another set of problems. It's a new house for me, so rather than do anything right away, I'll see how the boiler responds to the colder weather. For now, though, I'm not happy with the short cycling. Thanks again.


  • soot_seeker_2
    soot_seeker_2 Member Posts: 228

    My small house is equipped with 144EDR of radiator, currently steamed by a WM EG35, which is rated at approx. 254EDR. I have a lot of respect for the professionals on this board, so I would like to get your thoughts on downsizing the EG35 to EG30 output (192EDR). The two boilers are pretty much identical dimensionally except that 1) the EG35's manifold has 4 burner orifices, while the EG30's manifold has 3, and 2) The draft hood on the EG35's is larger.

    I'm a stationary engineer by trade, having worked with larger high pressure boilers, and I know how to use combustion analysis tools. If I were to 1) do a combustion analysis before, 2), change out the EG35's manifold and draft hood with an EG30's components, and 3) do a combustion analysis afterward, do you think that this would be safe? I'm not looking for anyone's blessing, just would greatly appreciate the feedback of people with a lot more experience in home heating than I have. Thank you.
  • Robert O'Connor_12
    Robert O'Connor_12 Member Posts: 728

    I belive you can switch gas train assemblies for everything else is the same. I'd contact a local WM dist. for price, this may not pay for itself anytime soon because your not reducing the input by much. I do like the way your thinking though.

    Good luck!

    Robert O'Connor/NJ
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