This is a new thread in response to a discussion on scraping the burnpot on the Enviro M55. started here: http://www.hearth.com/econtent/index.php/forums/viewthread/89616/ Long story short. The inevitable buildup of carbon on the burnpot drove a little crazy Crazy enough that I gave it a lobotomy, now we feel much better. %-P I have run my stove for almost 2 heating seasons. Pellets quality matters to some degree. Regardless of all the various factors that come into play. I have found that carbon generally builds up in the burn pot in two places: at the tab in front of the ignitor and the side of the burn pot towards the front of the stove. Both of these spots have very little air flow. I believe the ignitor only feeds air to the fire during the ignition process, then nothing after that. The buildup towards the front of the stove rarely comes in contact with the agitator, because its higher up on the sidewall of the pot. The spot at the ignitor is lower in the pot so it comes into contact more often. I have seen a post by Benski (I think) showing the center prong worn down considerably. I inspected mine and sure enough it is probably 3/16 shorter than the others. The agitator is not intended to be a carbon scrapper but more to clean ash out of the pot. I have resolved this problem and was going to post after I was certain it worked. Well here it goes. This isssue drove me a little crazy, so after much thinking I modified the burn pot with a single 1/8 hole drilled right through the tab in front of the ignitor. Going on two weeks now, burning a variety of pellets on high/lo and auto/off. Not a single scrape of the agitator on the this spot. The additional air prevents pellets from sitting and smoldering in this spot.