First, thanks for this forum. I discovered it about two months ago and have been trying to troubleshoot my issues. I have a Harman Accentra insert pellet stove, ser#008240329, manufactured July 2008 and installed that fall, by me. I built a corner fireplace and the insert is in a zero clearance box. I do not have an OAK, however, the hole is open that the intake would bolt to on the zero box, and I have a 4" hole that goes into my crawl space. Glued screen to keep the critters out. I have a 2' vertical pipe with a 90 and then a 2' horizontal pipe exiting the house, ending with a 45. I have read many problems similar to mine, to no prevail have they worked for me. I have had this issue since the stove was brand new and I'm not going to get into a rant about my dealer. He's a nice guy, he just can't figure it out. On my start up the auger runs for approx 45 seconds, and fills my burnpot, upon ignition I get a good flame. After about an hour my flame has traveled to the back of the burnpot and barely burns above the auger, still have a good flame. I get a really hard ash build up in the bottom of the pot and then partially burned pellets get pushed out into the ashpan, it gets worse if I leave it. I can't even come close to a 1" ash. I purchased a draft meter and the max is 1" wc, when I test the draft it pegs out my meter and never drops below 1"wc. Even when I attempt adjusting the draft screw. My dealer doesn't own a draft meter, he swears by the came from the factory calibrated. This is what I recently did after reading some threads. Checked ignitor for installation backwards, took a torch tip cleaner and cleaned all burnpot holes, cleaned ESP (which was very clean), and did a check of feed rates with a stopwatch. With the stove in STOVE mode, fan high, heat set on 7, ignitor on auto, the following rates were recorded (+/- 2 seconds); #2 OFF 48 Sec ON 13 sec #3 OFF 43 sec ON 18 sec #4 OFF 46 ON 21 #5 OFF 50 ON 18 #6 OFF 43 ON 18 I know the ESP temp controls the rate, I waited half hour between feed rate adjustments to level out stove. A new circuit board was installed winter 2011, to see if the problem.That's the only piece to be replaced except for an ignitor last season. No difference in the performance. I have to empty ash pan every two weeks, and I also do routine maintenance every two weeks, and my annual clean. I have actually been doing the annual clean twice a season. I'm so tired of all the wasted pellets and hard ash build up, and my glass is filthy in two weeks. Sorry for such a long post, I just wanted to try and cover all I have tried.