US Stove 6039, maybe 10 bags run through it this season--has smoked back in the house 3 times (twice over the weekend) after shutdown this year. Stove got the full teardown/clean/leaf blower treatment at the end of the season last year. Only change is the pellet from last year to now.....Rocky Mountains last year, OHP currently. What am I missing? Unit runs approximately 30 minutes after I hit the off button. I did take the feed rate to 1 (of 9) 15 minutes before shutdown and open the damper a bit to clean out the burnpot last night, but she smoked back anyway. Last year the only times I can remember it smoking back after shutdown were when I forgot to pull the damper all the way out when I shut down the stove--left smoldering pellets in the pot. Doesn't seem to care recently if the damper is full open or not......