Found it. It is referring to when shutting down the stove. Which is what I read as unattended. My bad? page 20 of the ESW instruction manuals. 10. Should I close or open the air control fully when shutting down the stove? When shutting down the stove, fully open the air control. This will allow chimney temperatures to remain as high as possible for as long as possible. Remember, cold chimney temperatures create creosote. So if I'm leaving the workshop and let the fire burn out, I'll leave the intake wide open; but I also haven't re-loaded the stove before I leave.