Ok, this stove was in my home when I bought it and wasn't working properly from the get-go. I replaced the mother board and it began working very well for a while (only been using it for about 3 months now). I noticed it was having issues, so I pulled it out, cleaned out the flue pipes, exhaust fan and housing, "trap doors", places behind the asbestos brick material, etc. and it was doing ok, but now, using a high quality hardwood pellet, the burn pot keeps loading up. I set it to final cleaning and when it's done, totally clean out the burn pot and ash tray, only to have it do it again and again after several hours of burning. It has no codes, no beeps. Any ideas what might be causing a poor burn?