Heating systems for new home

[FlyingScot]

Originally Posted by Slickcraft

Our hyper heat units 100% crossover efficiency is at about 0 deg F and they are good for operation down to minus 13 deg and 85% efficiency. However, when the temp drops below 0 deg I shut them off and switch to oil heat for zones not covered by the pellet stove. So I would not run them this Friday night.

Alan

I have never had mini splits in the same home as oil, so unable to do a direct comparison, but I am confused by your math or maybe by terminology. If mini splits are, say, 30% (or more) more efficient than oil, and they are operating at 85% efficiency at -13, aren't they still more efficient than oil at that temp? Thanks