Waterheatertemp

I get asked this question frequently. I hope this article will help you to increase the efficiency of your home.

Lower Water Heating Temperature for Energy Savings

You can reduce your water heating costs by simply lowering the thermostat setting on your water heater. For
each 10ºF reduction in water temperature, you can save between 3%–5% in energy costs.

Although some manufacturers set water heater thermostats at 140ºF, most households usually only require
them set at 120ºF. Water heated at 140ºF also poses a safety hazard—scalding. However, if you have a
dishwasher without a booster heater, it may require a water temperature within a range of 130ºF to 140ºF for
optimum cleaning.

Reducing your water temperature to 120ºF also slows mineral buildup and corrosion in your water heater and
pipes. This helps your water heater last longer and operate at its maximum efficiency.

Consult your water heater owner's manual for instructions on how to operate the thermostat. You can find a
thermostat dial for a gas storage water heater near the bottom of the tank on the gas valve. Electric water
heaters, on the other hand, may have thermostats positioned behind screw-on plates or panels. As a safety
precaution, shut off the electricity to the water heater before removing/opening the panels. Keep in mind that
an electric water heater may have two thermostats—one each for the upper and lower heating elements.

Mark the beginning temperature and the adjusted temperature on the thermostat dial for future reference. After
turning it down, check the water temperature with a thermometer at the tap farthest from the water heater.
Thermostat dials are often inaccurate. Several adjustments may be necessary before you get the right
temperature.

If you plan to be away from home for at least 3 days, turn the thermostat down to the lowest setting or
completely turn off the water heater. To turn off an electric water heater, switch off the circuit breaker to it. For
a gas water heater, make sure you know how to safely relight the pilot light before turning it off.

Reference U.S. Department of Energy topic 13090