Mini-Split Sizing Based on Historical Energy Use
I’m looking to install a pair of Mini-Splits to heat a 1550 sq ft bungalow with finished walkout basement. It’s 1968 construction. I am getting a variety of size proposals and I ran loadcalc.net, none of these values seem to align.
Currently we heat with mostly with two gas inserts (about 35kBTU each), one per floor but the primary heating is electric BB (27kW total capacity) which don’t get much use.
The space on both floors is largely open with a couple of bedrooms that we like cool in the winter and don’t use the BB. Circulation is by convection through all spaces, i.e. no forced circulation other than the fireplace fans.
My question is how useful are historical energy consumption (combined gas and electricity) at sizing new mini splits. For example, I used an average of 19kBTU/hr (equivalent) continuous energy in the coldest winter month. Is this useful in sizing a mini split max capacity and how would I do that?
Any insights will be appreciated.
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