Adjust the thermostat to 120 degrees. You’ll save up to 5% in energy costs for every 10 degrees you lower the temperature, plus you’ll reduce the risk of scalding.

Always maintain 2 feet of clearance around the appliance unless the manual specifically states otherwise.

Drain about a quarter of the tank a few times a year to remove sediment and debris. Turn off the cold water supply, hook up a garden hose to the drain valve, then run into a bucket until the water is clear. If the water remains cloudy, briefly open the water supply valve to stir up remaining sediment, and drain the tank again. This also makes the unit operate more quietly.

Annually test the temperature-pressure relief valve by quickly discharging it two or three times. Following the testing, keep an eye out for small leaks from the valve.

Examine the sacrificial anode rod every three years by loosening the hex head screw and removing it. Replace the rod if:

  • More than 6 inches of the core steel wire is exposed.
  • The rod is less than 1/2 inch thick.
  • The rod is coated with calcium.

You can buy a 13-inch zinc-aluminum anode rod for about $16.

Insulate older units with a fiberglass jacket to improve efficiency, being careful to avoid contact with the flue (newer units already are insulated — check your owner’s manual to make sure). Also, insulate the hot and cold water pipes.

When leaving town, adjust the thermostat on gas heaters to “vacation” setting, which maintains the pilot light without heating the water.