First post to the forum... I've been reading and leaning a lot so far. Just got my Breckwell SP6000 and after reading through the manual multiple times I have yet to figure out how to exactly clean the heat exchange tubes. I called Breckwell and they told me to run a soft brush down the inside of the tubes in front where the heat gets blown out. Correct me if I am wrong but there really wouldn't be any buildup on the inside of these tubes would there be? I was under the impression that cleaning the heat exchange tubes was clearing any buildup of creosote on the outside of those tubes. I am confused.