> you have that problem with all heating and cooling This is probably regional, but in Canada it is common to have heatpumps/AC for cold and electrical heating

> you have that problem with all heating and cooling This is probably regional, but in Canada it is common to have heatpumps/AC for cold and electrical heating/furnace for heat. That means your cold is coming from the top of the wall (where the wall unit is) and your heat is coming from near the floor with baseboard heaters. That gives you a better mix of air and a better overall comfort. Furnace exits also tend to be embedded in the floor at the bottom of a wall/window. Wall mounted heatpumps mess with that paradigm because the air, whether hot or cold comes in near the ceiling. That actually works great for cold, but whn heating the hot air simply won't come down. If you have a second floor it will instead heat up that second floor. It's not the worst thing in the world, but you definitely have a large temperature gradient from the first floor floor to the second floor ceiling that is noticeable. Especially when going down the stairs. In my case it will be around 19-20C at the lowest point and 23C at the highest.