Water Heater / Heat Exchanger Corrosion?

[jkindredpdx]

I see water heaters with Aluminum Tanks and Galvanized Steel or Aluminum Case. Wouldn't aluminum tank in an aluminum case be preferable to avoid galvanic corrosion from mixing aluminum and steel?

[ValiantV]

Ideally, the tank would be separated/insulated from the case by the tank insulation. Whether that is actually the case is a question someone who had had one apart would have to answer.

[Calif.Ted]

The covers don't contact the tank and don't show, I use the galvanized covers because they are cheaper and the Aluminum tanks fail every 10 years, never had a cover "fail".