On Sun, 10 Feb 2008 22:20:41 -0700, Rick Blaine wrote:

Consider the case where one heater has poor insulation and a very
efficient burner, and the other has a poor burner and better insulation. Both
have the same EF, both cost the same to operate over a year. Which one do you
buy?

I thought MORE about what you wrote and you're ABSOLUTELY RIGHT!

The insulation was suggested by someone else (not me). I agree with you,
the thickness of the insulation, in and of itself, is as meaningless as the
volume of the tank, in and of itself.

What seems meaningful isn't the warranty.
It's not the volume of the tank.
It's not the thickness of the insulation.
It's not even the total energy costs (since they make assumptions which
might not be true).

What seems meaningful is the ER and the FHR which take into account ALL
those factors (and more).

So my conclusion (open for discussion) is that what matters is:
- Get the desired FHR needed (e.g., 65 to 75 gallons is fine for me
- Get the desired ER (I wish I could find a .62 instead of .59 ERs)
- Get the right PHYSICAL SIZE (e.g., a 40-gallon tank is 50 inches tall)

Some other factors which _might_ be interesting a
- Your article said try to get an ELECTRONIC flame igniter
- The Home Depot guy tried to sell me on the maintenance-free ones
(He said they had a fan that stirred up the sediment)
- Some folks recommended "better" valves for cleaning out the sediment

Donna