I need to replace the liner in my chimney among other things. Connected to the Chimney I have two Mid-efficiency Gas boilers (125K & 100K BTU ~80% AFUE each) and two water heaters (I think 40K BTU each but not 100% sure).
I got 3 estimates and two of the three contractors is thinking of using aluminum liner and the other one recommended stainless steel.
My question, which way should I go Aluminum or Stainless Steel? I asked the two contractors and they said for this my situation aluminum should be fine and that stainless steel is normally for oil boilers or devices producing a lot of heat. Also they gave 25yr warranty on the liner. Please let me know what you think.