Tankless water heaters are also called “on demand” water heaters, and that gives an important insight into how they work. They heat water only as it is needed. The absence of a tank in which hot water is stored and continually reheated, even when there is no demand, means that there is no standby heat loss whatsoever. Instead, the tankless water heater transfers heat to the water as it circulates through the heating component, known as a heat exchanger.

The heat in the exchanger is generated either by electric coils or a gas fired burner – natural gas or propane – to quickly and effectively heat water from a cold water feed. There may be 20 feet or more of water pipe running back and forth within the heat exchanger, giving the unit ample time to heat the water. The exchanger is activated only by the flow of water when someone turns on a faucet or appliance that is fed by the unit. Because of the way they function, tankless water heaters have the ability to supply a steady flow of hot water without risk of it going cold.

There are two basic styles of tankless water heaters. Whole house water heaters have a larger capacity and are able to supply continuous hot water to several applications at once – faucets, showers, and appliances. Point of use units supply hot water heater to one or two application points located in close proximity, such as in a bathroom or kitchen.

How Tankless Water Heaters Work Video

Learn more:

Tagged with:

Filed under: Articles & Buying Guides