I have lived in my house 3 years and have used my woodstove with no big problems. Chimney cleaner #1 came the first year and said it looked ok but maybe needed a new liner soonish. Chimney sweep #2 came this year, tells me there are cracked tiles and the chimney is unusable right now, and that he can’t put a liner in because it appears the chimney flue itself is only 6”. You can see in the chimney that and old liner of some sort is deteriorating in place. I’m in touch with the former owner of the house. He tells me “3 decades ago I put an 8” stove pipe down the chimney and poured cement slurry around it.” So that’s what we’re dealing with. Going to have chimney sweep #1 return for a second opinion. But is there any advice here for this situation? #2 doesn’t think he can get a new 6” liner in there. Any alternative liners I might look into? How safe (assuming structural integrity intact) is 30 years old cement around stovepipe? Chimney is brick but behind drywall on the interior.