As long as the unit fits into the vent and there is an electric receptacle close by, the device will work both in floor and wall vents. Since our solution is a smart fan (and not dampers) it is okay to have some clearance around the device and having empty space around the device will not affect the way the device works. If you are having trouble with the Installation you can refer to this video https://www.youtube.com/watch?v=dDDAeAdAQAg
Also in the ceiling vents, the device can be used if it is safely secure behind the grill and is connected to the power.