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water heating





bathroom shower
Water heating is the third largest domestic energy expense. It accounts for about 13% of the average American home utility bill.

There are four ways to cut your water heating bills: use less hot water, turn down the thermostat on your water heater, insulate your water heater, or buy a new, more efficient water heater.


Water heating tips

  • Install aerating, low-flow faucets and showerheads.

  • Repair leaky faucets promptly; a leaky faucet wastes gallons of water in a short period of time.

  • Lower the thermostat on your water heater; water heaters sometimes come from the factory with high temperature settings, but a setting of 120F provides comfortable hot water for most uses.

  • Take more showers than baths. Bathing uses the most hot water in the average household.

  • Insulate your electric hot-water storage tank, but be careful not to cover the thermostat. Follow the manufacturer's recommendations.

  • Insulate your natural gas or oil hot-water storage tank, but be careful not to cover the water heater's top, bottom, thermostat, or burner compartment. Follow the manufacturer's recommendations; when in doubt, get professional help.

  • Insulate the first 6 feet of the hot and cold water pipes connected to the water heater.

  • If you are in the market for a new dishwasher or clothes washer, consider buying an efficient, water-saving ENERGY STAR model to reduce hot water use. See Appliances for more information.

  • Install heat traps on the hot and cold pipes at the water heater to prevent heat loss. Some new water heaters have built-in heat traps.

  • Drain a quart of water from your water tank every 3 months to remove sediment that impedes heat transfer and lowers the efficiency of your heater. The type of water tank you have determines the steps to take, so follow the manufacturer's advice.

  • Although most water heaters last 10-15 years, it's best to start shopping for a new one if yours is more than 7 years old. Doing some research before your heater fails will enable you to select one that most appropriately meets your needs.

  • $ Long-term savings tip: Buy a new energy-efficient water heater. While it may cost more initially than a standard water heater, the energy savings will continue during the lifetime of the appliance. Look for the EnergyGuide label.

  • $ Long-term savings tip: Consider installing a drain water waste heat recovery system. A recent DOE study showed energy savings of 25% to about 30% for water heating using such a system.

  • $ Long-term savings tip: Consider natural-gas on-demand or tankless water heaters. Researchers have found savings can be up to 30% compared with a standard natural-gas storage tank water heater.

  • $ Long-term savings tip: Heat pump water heaters are very economical in some areas.
average hot water use


For more information see:

Selecting a new water heater


Provides information about choosing a water heating system that will not only provide enough hot water but also that will do so energy efficiently, saving you money.


Energy-efficient water heating


Features strategies to help you decrease water heating costs in your home.


Related category

   • HEATING TOPICS