Ok here is something I have had happen two times. The unit ended up on as a result of the thermostat calling for heat at a given time, I knowing we don't need the unit on turn the temp down, after the unit has been burning for a short time, For what ever reason it dumped the ash into the pan while there were smoldering ash in it, and even though I have an out and up setup it smolders under the fire pot in the ash pan and results in a smell in the house, not a lot but enough. has this happened to you?