There are different benefits to different placements of a Daikin Air Purifier and each will depend on your own desired purpose. To remove house dust, it is most effective to place the unit at a lower position in the room. To remove cigarette smoke, it is more effective to install the unit in a higher part of the room. Furthermore, if you install the air purifier opposite an air conditioner, circulating air is cleaned during cooling and heating operations of the air conditioner. Identifying which of the above best suits your needs will help you make an informed decision in using your Daikin Air Purifier.