Whirlpool 9 year Energy Smart Electric Water Heater

Anode or Anode Rod

Sacrificial component made of aluminum, magnesium, or other alloys, that is corroded by electrical currents in order to protect the inside of the tank.

Control Circuit

Parts that measure tank temperature, direct the unit to begin heating and provide safety controls to prevent overheating or other unsafe operating conditions.

Dielectric Connections

Water connectors that reduce the flow of electricity related to galvanic corrosion, from the house piping to the water heater.

Department of Energy (DOE)

Government agency that regulates water heater efficiencies.

Energy Factor

Overall efficiency of a water heater calculated by testing tank draw efficiency, recovery efficiency, and standby efficiency using the DOE protocol.

Energy Guide Label

Yellow label displayed on every water heater that compares that model's energy use to similar models.

Expansion Tank

A tank installed on the incoming water line that absorbs expanding water and prevents pressure build up inside the water heater.

Gallons Per Hour (GPH) Recovery

The amount of water, in gallons per hour, that a water heater can raise by 90° increase in temperature.

Kilowatt (KW)

Measure of electric power. 1KW = 1,000 Watts

Mixing Valve (Tempering Valve)

Device that mixes cold water with hot water supplied to general use fixtures.


Threaded fittings provided on some models for incoming and outgoing water pipe connections. Most models utilize 3/4" water connections.

Potable Water

Water that is suitable for drinking because it contains nothing harmful.


Salts formed and deposited inside the water heater or on fixtures. Sometimes referred to as lime deposits.


Very high temperatures at the top of the water heater tank caused by increased cycling of the burner or heating elements during short draws of water.

Temperature and Pressure Relief Valve (T&P Valve)

Safety device that releases hot water when temperatures inside the tank reach 210°F, or when pressure exceeds 150psi.

Thermal Expansion

Expansion of water as it is heated.


Electronic device used in place of a mechanical thermostat that measures water temperature.


Measure of electric power. 1,000 Watts = 1 Kilowatt