Just kidding! I saw your post in the help section.
If there's no stainless steel in there, I wouldn't worry about it too much. With stainless, it will literally disintegrate before next season. Guess how I know that one ...
Like I said, if no stainless, just clean the chimney real good & I think you'll be ok. My decrepit masonry chimney has been breathing humid air from my basement ... AND I did not clean ANY fly ash out of it for 9 years. It's still standing .... barely ... but it's standing!