operating instructions? Although we get heat from it we bought a much more powerfull one than was neccessary for the room in the hope the heat would spread into another room next to it where the entry was open. We seem to be able to heat ne room but nothing else. The insert came with no operating instructions and i wonder what we are doing wrong. There is a little sliding piece in the top with a +~- and a fan wuth two settings also a metal handle to turn to openand close the tube but when to do that will closing it slightly give us more heat? Any help would be appreciated.