I'm planning on finishing a boiler install this Summer and thinking about relining at the same time. The boiler is capable of 89% + efficiency with flue gas in the range of 220F-275F degrees gross (not net) stack temp. Not quite condensing (so plastic is out of the question) but after spending the money on such an efficient appliance I DO NOT want to open up the air and push more heat out the chimney just to raise the temp. The existing chimney was built in 1994, is 8x8 clay lined in good shape. It is on the East side of the house, exterior on 3 sides, and about 20' from tee to cap. The new flue size will be 5", so relining isn't a bad idea because from what I've observed the current draft is not impressive.
I plan installing myself. I am going to insulate the new liner. My main question is what type of stainless to use. 316ti vs al29-4c alloy. I have read that 316ti should be fine for non-condensing oil boilers, and have read to the contrary as well. It seems if manufacturers are making condensing chambers out of 316ti it should be fine, and there's no reason for the added expense of a patented alloy with a premium price.
I plan installing myself. I am going to insulate the new liner. My main question is what type of stainless to use. 316ti vs al29-4c alloy. I have read that 316ti should be fine for non-condensing oil boilers, and have read to the contrary as well. It seems if manufacturers are making condensing chambers out of 316ti it should be fine, and there's no reason for the added expense of a patented alloy with a premium price.