This should be the last update. The Mitsubishi min-split models we have are supposed to produce 100% down to a -5 degrees F. This past January they got tested and preformed perfectly. We didn’t get to a -5 but did get to and near 0 a couple nights. We had a two week spell where it was exceptionally cold, 12 day with the night time low in the teens and single numbers and only in the 20ds during the daytime.. The one mini-split in the family room kept the house between 68 to 70 down to around 15 degrees F, below that we had to supplement it with the one in the bedroom. We’d run the bedroom unit from noon ish or late afternoon to 10:00 or 11:00PM. It was our highest electrical usage so far, 1,100 kWh compared to last Jan at 992kWh.. Our old house averaged 1,200kWh for all the winter months (which didn’t include heat nor hot water). Solar production was down a little because the penal were snow covered more days then last year.
Amazing performance. The house was comfy, no drafts. Now we are back to the cycle where the TV and cooking will, on some day produce enough heat to turn off the mini-splits in the evening and over night to the next afternoon.