"Daniel Prince" wrote in message
...

My understanding is that gas water heaters are made with glass lined
steel tanks and that they usually fail because the steel rusts out.
What I want to know is: How does the water get to the steel if it is
glass lined? Does the glass lining have holes and/or cracks in it when
it is new? Do holes and/or cracks develop later? If the holes and/or
cracks develop later, how and why do they appear?

....etc.

Check out the following website.

http://www.waterheaterrescue.com/