Water Heater Tune-up

The main cause of water heater failure is sediment buildup in the
tank. Often there is sizzling and popping when the element heats up --
as it works harder to heat the water. This not only wastes energy but
often causes early replacement, as well. You can save money and extend
the life of your unit by occasionally draining the tank and flushing
away sediment. Here's how: for electric heaters, turn off the power,
for gas turn the control to ?pilot.? Next, turn off the cold-water
inlet valve and attach a garden hose to the outlet valve at the
bottom. You'll be running hot water, so be careful. Then, open a
nearby faucet to improve flow. Once the water drains out, reopen the
cold-water valve to flush the tank, then reverse the process, turning
faucets off last. Check your thermostat (it should be no more than
120°F). If you take these precautions, a water heater that might have
lasted only 10 years could last 15 or more. And that's the On The
House tip for today.

http://www.onthehouse.com/tips/20090309