Have you changed the element & thermostats without concluding that they were actually defective? That's why DIY repairs often work out more expensive than calling service in the first place. I really admire people who are willing to "give it a go" but sometimes...horses for courses is the best way to travel.
The full tank warning light has nothing to do with the heat problem. This is probably due to a clogged pump/water chamber.
Mike
November 2009
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