Try to use cold water whenever possible When using small amounts of water, keep the lever on the kitchen faucet set to COLD, especially when hot water has not recently made the trip from the heater to the faucet.  In this situation, moving the lever to HOT let hot water enter the supply line even though the hot water never reaches the faucet and the water heater must warm the cold water that replenishes the tank.

Don’t heat water unnecessarily if you’re out of town
Whenever you leave home for a weekend or longer, there’s no point in heating water that no one will use.  Either set the water-heater thermostat to its lowest setting or turn off the water heater altogether.  Reset the thermostat as soon as you return; you’ll have hot water again in an hour.

Repair leaky faucets
A hot-water valve that leaks just one drop per second can waste as much as 400 gallons of heated water a year.  The cost of that wasted ends up on your utility bill.  Repairing leaky faucets is a cheap way to save both money and energy, especially if you do the work yourself.

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