For the best position, you have to know which place needs. First, you have to fix a place where you want the best air to circulate. Even you can choose throughout your room. The upper part of a wall is the perfect place for an excellent position for a Daikin wall mounted aircon unit. But the too high rank is not suggesting to make sure the indoor unit is easily accessible. You can discuss it with your aircon specialist. He can recommend you the best option, to know your all requirements