I watch the boards but don't post much and I don't believe I've seen anything about giving the stove heat exchanger passages a good cleaning. I'm talking about the passages up behind the impingement plate (Baffle). I've tried vacuum tools, and a test tube brush with a 8" handle but it still doesn't seem like I can reach to the bottom of these passages. Does anyone have a special trick or method to get all of the soot out of the passages. I'm imagining that if they are partially clogged this will decrease the amount of heat transferred to the room air and thus less heating of my home. Any suggestion would be welcomed.