This is a common headscratcher in the heat pump space. They're taking advantage of a thermal gradient to get more out than they put in. Very much like driving

This is a common headscratcher in the heat pump space. They're taking advantage of a thermal gradient to get more out than they put in. Very much like driving downhill, as I understand it. If you put an air conditioner into a closed system, you can't beat Carnot efficiency. But if you're allowed to dump/absorb heat to/from the environment, the coefficient of performance measures the heating/cooling on the control side versus energy input -- which is allowed to go over unity. https://en.m.wikipedia.org/wiki/Coefficient_of_performance https://en.m.wikipedia.org/wiki/Coefficient_of_performance (I'm no authority here -- I only bought a heat pump and had the same reaction as you)