Mine hums like a fridge. Luckily, its straightforward and normal for the heat-pump to be outside or in a garage or basement, so the sound isn't in the living s

Mine hums like a fridge. Luckily, its straightforward and normal for the heat-pump to be outside or in a garage or basement, so the sound isn't in the living space. Its like: who would want a window-mounted air-con when they could have one of those white boxes up on the roof where nobody hears them instead?