On 30-Mar-2004, "daestrom" wrote:

Exactly right. This is the same as 'setback' thermostats. There *is* a
savings, but it is difficult to calculate/predict the results.

I agree. However, the temperature drop in a house over an 8 hour period could
easily reach 25 degrees (assuming sub-freezing temperatures outside), and the
energy cost from heat loss of a whole house is much greater than the cost of
heat loss from a water heater.