Hi All, I have 1 detector and have it in the same room as the pellet stove just sitting on an end table because I can't decide where the best place is to put it. It's a 3 bedroom house, 1 bedroom on the first floor, same floor as the stove and 2 bedrooms upstairs with stairwell. I'm thinking about buying another one. Should they be placed near the ceiling just outside of the bedrooms? Thanks for your help.