50s hot water best case scenario

Russ_8

WARNING! I don't know anything about this, but my BS alarm went off. Anyway my church had its 1950s vintage hot water boilers refurbished with new burner controls and whatever else you do to old boilers to make them "like new". The heating contractor is claiming these are now 95% efficient. I can't allow myself to believe this figure; almost nothing I can think of is 95% efficient. Any idea what the best case efficiency for these old dogs might be assuming a great contractor, proper sizing, tip-top mechanical condition, 21st century controls, everything else done right, etc.? Maybe these are that good?

Boilerpro_3

Limits of Physics

Unless they are designed to be condensing boilers, standard boilers will top out at 87% firing efficiency or so on a combustion analyzer. However, your real life efficiency over the heating season is effected by how often the burners cycle, standby losses, and alot more. I have done extensive work with churches, and have replaced some of those old dogs that tested out at 87% with small, stage fired multiple boiler setups and up to date system controls and save from 35 to 75% percent. True efficiency is a combination of clean burning, heat transfer to water in boiler, stand by losses, transfer of heat from water to heating units in spaces, and then tranfer of heat to spaces, and the type of heat deliver to the spaces. Ther are only a couple of boilers that can achieve 95% efficiency by any standard and that is only under particular conditions.

Boilerpro

jerry scharf_3

no need to reset your BS detector

It seems to be functioning quite well. Even if the boiler was run into condensing mode (which would rapidly destroy it,) it could still not approach that level of efficiency.

jerry