Hello, I have a Hearth Stone Phoenix stove with a build date of 1993, burning wood that has been split and in a covered shed for about a year and a half and after just two weeks of burning the chimney pipe was super dirty, to the point that I had to clean it because the creosote had started to peel away from the walls and block off the pipe. My question is could there be something wrong with the stove because I can never seam to get it to do the secondary burn? Any help would be greatly appreciated.