Yesterday I woke to an overflowing burn pot and more pellets burning outside than inside. First time that had happened. Although I have had some days with pretty large clinkers after 10 hours. Shut the stove down, cooled and did a weekly maintenance. The burn pot had a carbon build that I've never had before. Scraped and brushed pot and vacuumed, including the hidden chambers. Four o'clock in the afternoon, full again and a lazy, weak flame. Anger rising. Clean burn pot, checked for excess ash, none, and relit. Lazy flame with full open air supply. Now I'm remembering my concern that the old exhaust fan may not be up to it. Thinking about needing to replace, but I'd like to get through the season. Cleaned the pot at mid-night before turning in. Woke up at 7 and we're dirty again. Crap, maybe the ash is caking the fan and if I clean it we'll be OK. Ran the stove until 3:00pm when I took a work break and went after the blower. Pain to remove, need to pull the stove and take off the back. Freed the blower and tuned it over, almost no soot. Less than 1/32 on blades, almost nothing in the housing. Well, I got a little excited. Broght in the big collector, 6inch hose (used with the planer), and a line from the compressor. I was going to strip the ash, soot and anything else out of it. The long and short is, brushed first, vacuumed, then set the 2HP collector and 150psi of air loose on the stove. Didn't exactly get a cloud, but the big suck kept the duwst contained.I mean, it took shots to every nook and cranny. Thirty minutes of cleaning with air. Reassembled and was looking forward to a much improved burn. Took thirty minutes to fire up. No previous settings for air and feed rate worked. I mean it wouldn't start. So, I cut the combustion air back, left the door open and coaxed a fire. Got it going and spent a half hour coaxing a good fire. So, as of 6pm, I have a VERY clean running stove. My combustion air setting is about 40% of the range, and the pellet feed rate is maxed to warm things back up. My thinking is, I won't have to replace the motor, I won't have to worry about keeping things running, but brought up an issue I have never thought about. Doing the manufacturer recommended cleaning is not enough. I have a stoe that operates better than when I first bought it. Now, for all you skeptics, I know what triggered the problem. I bought thirty bags of pellets from Lowe's, same as I have used all this year, Eureka. The store threw in a few broken/partial bags. I assumed they were broken, not returned. I've been burning the partial bags, so I don't have a storage issue. Didn't seem right texture. Well, I opened a fresh bag from the same pallet, and compared. The partial bag was crumbly and mealy. They were not good pellets. The fresh bag was hard and dense. I could not crumble them with my fingers. Burning a few bags before my friends from Idaho come to claim their share. Want to make sure they are happy, don't want to miss the Dinner.