there are these inner tubes that are like solid rubber but i don't know what there called
it's also sensitive to heat, which you trapped under your hat. it should be put as high as possible because heat and smoke rise to the ceiling. the farther down you put it means that the smoke has been going on for sometime before you would be aware of it. as a matter of fact by that time it my be too late. think about it. you always find them on the ceiling or high on a wall. those who taped a plastic bugs over their detector are idiots. how is the smoke supposed to get into the detector? a little cigarette smoke won't usually set it off. open a window and blow the smoke out with a fan. that's a disaster waiting to happen. good luck to ya and put it higher.
Have your furnace checked by an hvac pro.You might have a cracked heat exchanger.Get a carbon monoxide detector also.
