New poster to this site. When I got my house, the owners left a Whitfield Quest Pellet Stove. They hardly used the thing. Well Ive been using it for 5 years now. Last year had to have the air up all the way and pellet speed on its lowest setting. Paid a guy to come and fix it. Well he cleaned some stuff (I wasnt here unfortunately) and it seemed to be buring good when he left. Well that lasted a day or two maybe and it was right back to the way it was. SO I am in the process if tearing it apart. Took off the blower motor on the right side revealing the air damper valve. Some build up there. Cleaned that and took off the assembly where the air damper valve is and got to the back side of the wall. There is a small square opening. Got a tooth brush wedged in there and cleaned what I could. Tapped the front of the wall with a hammer. My question is on the front side, Ive taken the brick out. I was going to see whats involved in getting to the heat exchanger tubes, I broke the one of the two bolts holding the plate thats below the tubes. Do I need to be cleaning something under the tubes/in the exchanger tubes? Ive tried to read as much as I can but havent been able to find a lot on the Quest models. Any help would be appreciated