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Fuel waste if boiler size exceeds capacity of radiators?
My current gas boiler is massively oversized – 175KBTU/hr. Using the EDR calculations kindly provided by someone on this forum, the maximum output of my radiators is about 75K BTU/hr. Putting aside for a moment that the heatload calculation for the house is even lower, what happens to the extra 100K that the boiler tries to put out but that the radiators simply cannot radiate? Is that all wasted fuel?