Ook wrote:
Labor can't replace material. Its called a "sacrificial" anode for a
good
reason. See he
http://www.waterheaterrescue.com/pages/WHRpages/English/Longevity/water-heater-anodes.html

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Grandpa
Why do they call it an anode?
http://en.wikipedia.org/wiki/Anodes


I know what an anode is. I also know what a cathode is. But that doesn't
answer my question....I stick this rod in the middle of my water heater -
what makes it an anode, and not a cathode?

Then you don't really "know" what an anode (or cathode) is...

It's an anode if it attracts anions, and a cathode of it attracts
cations...I'm pretty sure that's the definition you know. (DOH! )

Which, of course is sort of a circular definition. What actually makes
it one or the other is the relative position on the scale of electrical
potential of the material from which it is made with respect to the
other material.

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