In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
I agree the tanks these days seem to bve thinner gauge, and I wonder that the glass lining isn't thinner. The life will be gteatly ndependant on the water quality, amount of fresh water it sees, the delta t, and the output temperature, to name a few.
I think a basic glass lined steel tank should go 8- 10 in a residential installation. After that they may be so full of sediment (percolating sounds) that a replacement may be money well spent for efficiency gains.
If you were a, glass lined steel tank, water heater manufacture, how long would you design your tanks to last. Therein lies the answer to your question, I think :)
Even high tech stainless tanks have limitations.
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