. So y'all know I'm the noob here, I've been cleaning the daylights out of my new to me accentra. Along with the stove I got quite a bit of exhaust pipe. It was all really, really dirty inside. It was laying outside under the guys covered porch when I went to pick everything up. I picked up one end of a 4 ' length and got a huge pile of soot out . This had been hooked up to his pf100, so it saw a lot of use. In any case I want it as clean as possible before I do my install. I bought the 3" flue brush and ran that through it a few times and it did really well, but I wanted better. I took a small bucket, put in some screaming hot water and some dawn, I kept dunking the brush and scrubbing the pipe and then rinsed it out with some more clean hot water. I'm absolutely shocked! This stuff looks excellent. The inside shined up just like brand new, no gook, no dust no nothing. That should go a long way in helping this stove run the best it can. It also speaks to the quality of the steel that Simpson/duravent used in this product. Theses pipes are date stamped from 2003 and they look great inside. Try and get a barbaque to last 5 years....this stuff is 12 years old with a ton of use on it and is as good as new.