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

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

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

Government agency that regulates water heater efficiencies.

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

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

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

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

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

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