AO Smith Conservationist "Gold Edition" 40-gal NG WH

It was installed 10/99 and had a 5 year warranty. The water is very hard. No noticeable problems with it so far, but I am wondering if I'm on borrowed time with this one because of the short waranty?

I can't provide hard data to back this up, but if I had to guess, I would say that on avarage, a water heater is good for minumum 10 years. There is very little if anything of significance different between your model and another they probably sell with a 10 or 12 year warranty ( except of course the price).

When a WH gets to 12 years old, I can recommend replacing it "just because" if it gives someone peace of mind. At 7 years old, well beyond infant morality range, I believe you have an equal chance that a new water heater installed now would fail before the old one would have.

wh

It is the standard warranty, not a short one. The heater's life depends on your usage and the quality of the water, but in this area gas heaters last from 10 to 15 years. Electric ones can fail within 6 to 8 years.