Tankless water heaters provide hot water on demand using a powerful heat exchanger that increases the temperature of the liquid as it passes through the tubes in the unit. They are available in electric, natural gas and propane models. Some units are whole-house models, while others are point-of-use systems.Continue Reading
One of the advantages of the tankless system is an endless supply of hot water. Since the unit heats water instantaneously, it does not run out of hot water regardless of the number or length of showers. However, point-of-use systems only provide water for one to two fixtures at a time. Whole-house systems are larger and more expensive, but provide hot water for using several fixtures at the same time.
Storage-tank water heaters, commonly used in the United States as of 2014, use a smaller heating system to slowly bring the water in the tank up to temperature and maintain it there. A thermostat initiates the heating process when the water in the tank reaches the lower limit and stops it when the water reaches the upper limit. The water remains within the range continually, even when no one is at home. In contrast, the tankless water heater only heats water when the tap is open, eliminating standby heat loss.Learn more about Appliances