Minisplit Make and Model Recommendation
I am building a 1.5 story house in the midcoast region of Maine (CZ – 6), inland from the coast about 20 miles. It will be a double stud build insulated with DP cellulose (I have estimated a total wall R value of about 32), triple pane windows, and an R-50 ceiling/roof.
I estimated heat loss to be about 18,000 BTU/hr, including losses due to exfiltration. About a third of the non-exfiltration losses occur via the walls of the full basement.
I intend to heat primarily with wood so, in a sense, the heat pump is a backup system. That said, the unit needs to be capable of keeping things warm when I am away or can’t burn wood for some reason. In the past I have kept bedroom doors closed and have not actively heated the upstairs (2 bedrooms and a bathroom), I expect those habits to continue. The basement will be unfinished and unheated. I do not care about the cooling side of things wrt the heat pump.
Given the above, I am tending towards a a ductless unit on the first floor, and resistance baseboard heaters on the second floor. Others have suggested different approaches in prior Q&A but this seems like the right balance for me at this time.
With that all said, three makes/models of heat pumps have been recommended to me. They include the Mitsubishi MSZ-FS15NA and MSZ-15NAH and the Samsung Max Heat 18K (RNS18ABT and RXS18ACT) and 24K (RNS24ABT and RXS24ACT) models. The max heating capacities of the Mitshubishi model are 16K and 14.4K at -5 and -13 deg F. The corresponding data for the 18K unit are 17.7K and 12.5K, for the 24K unit they are 21.2K and 14.6K. The max heating capacities of one or more of the units are light relative to my heat loss calculations but I think I need to balance this with the fact that I am not trying to actively heat the basement or second floor.
Do any of you have any opinions about the appropriateness of these units (in terms of capacities, brand and model reputations, etc.) given my situation? Are there other makes and models worth considering in addition to, or instead of, these? Thanks for any help you can provide.
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