Water heating accounts for about 17% of the energy consumed in homes, and some businesses—such as hotels and restaurants—have very high hot water demands. Providing energy-efficient hot water for these different uses can be accomplished using a variety of technologies. The most efficient fuel-fired water heaters include electronic-ignition gas-fired tankless or on-demand models, advanced combination space- and water-heating systems, and gas-fired condensing storage-tank type water heaters.
Tankless water heaters have no standby losses, and some models have sealed combustion and use condensing technology. Some models can be used as boilers for heating in very-low-energy buildings. In combined or integrated systems, efficiencies are boosted by uniting space heating and/or cooling into a single system that includes water heating, and some boilers provide domestic hot water.
Products in Water Heaters
A. O. Smith Water Products Co.
Daikin AC (Americas), Inc.
EcoInnovation Technologies Inc.
ReTherm Energy Systems, Inc.