Looking for some help I just purchased a used Masterforge H3W80XL to install at my mothers house. I have one of these installed at my house and love it found this one for cheap on FB marketplace. The stove itself inside was CAKED with black sooty material and looks like it has never ever been cleaned. The stove was setting an E5 error come to find out the exhaust was plugged at the heat exchanger where it goes down to the exhuast i did my best to knock as much as i could from it to get good air flow tore the entire stove down as far as i could and cleaned it as much as i could. The area that was clogged is very difficult to get any tools to to clean it and at the exhuast there was a bunch of tarry creosote. I cleaned the exxhust fan area completele and swept the exhaust as far as my brush could reach on the stove and fired it up. It ran good put off good heat. My concern is where teh heat exchanger curves down to the back of the stove I want to get more of that ashy tar out of there until its clean any suggestions? Ive tired compressed air and a brush but the path to get up to it throug the two lower clean outs is very small. Do thos creosote pellets work? does just burning it on a high temp help clear it out? all input apreciated thank you!!