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Sizing for Hot Water Boiler
I am looking to replace an 17 year old Burnham V75 boiler with a Biasi B10/4. Trying to figure out the proper BTU needed and have done a bunch of heat loss calculations. I used CoolCalc, Slant Fin, and even the Weil McClain manual version. My house is about 2800 sq feet and was built in 1997 so well insulated with decent windows in Southern Maine. My old Burnham says Net IBR our 166,000. Seems way too big for my house. Plus I heat the 952 sq ft first floor living space with a pellet stove in the colder months. All my heat loss calculations at worst say around 77,000 btu if I use real liberal numbers. Any thoughts?