I have 8 Keen vents installed along with @yvesracine ScheduleRoomTempControl app and everything is working perfectly. Previously I could never balance the temperature upstairs and downstairs, but now I have everything working great. Now all my rooms are usually within 1 degree of each other. I do agree with @krv that you need a separate temperature gauge in each room, as the Keen vents are not even close, especially when heating. Everything I learned was on the thread at: