Tanks naturally build up sediment, which reduces efficiency and makes saving energy a challenge.
Draining the tank and saving energy is relatively easy. Turn off the water and power to the unit (set the burner on a gas unit to “pilot”). Connect a garden hose to the spigot at the base of the tank. With the other end of the hose pointed at your floor drain, carefully lift the tank’s pressure-relief valve and turn on the spigot; water should begin to flow.

While most manufacturers recommend draining the tank once or twice a year, you don’t have to drain it completely; in fact, the Department of Energy recommends draining less water more often—just a quart every three months.