Did a 6 hour test run today just to make sure its ago for the season.......after 5 hours of running window was dark enough to where i couldn't see the ash in the burn pot....im burning lignetics and my settings are 4-7-1 (englander 25 pdvc). i'm only concerned about the glass beacause i wanna be able to see how the stove is operating........am i doing something wrong or is this just how fast they blacken....thanks