"roperman" wrote in message
oups.com...

To remedy this, I installed a timer that turns on the water heater
once a day for an hour. The 40 gallons of hot water gets us through
the day (so far, but I just installed the timer last weekend). My
friend says this won't save any energy, because warming up the hot
water tank from a low temperature will take more energy than heating
it up throughout the day, where the temp differential is lower.

Your friend is wrong. It uses the same enegy to heat the water, and you lose
less heat when the water tank temp is lower. It may not be a big difference
though.

Bob