I've been burning 24/7 for around two weeks now. Wife and I are learning the stove and I know that we haven't burned optimal as the door glass has been cleaned three times. I cleaned out some ash this morning and immediately extinguished with water. There were some coals in the stove but not very hot so I decided to check the chimney. The very top of the liner seemed to have a sticky black substance. I could only see a few feet down as the coals were still smoking. Will this stuff burn off/melt when I get a real fire going or is this a creosote problem? I want to thank you all again, because of this site I am checking the chimney regularly and would never have thought to check. A sincere thank you.