Which type of boiler system heats water only as needed?

The instantaneous boiler, also referred to as a tankless boiler, heats water on demand, offering significant energy efficiency. When water is required, the system heats it as it flows through the unit, eliminating the need for storage tanks that hold pre-heated water. This approach allows for continuous hot water supply without the standby losses associated with traditional storage tanks, making it an ideal choice for many residential and commercial applications.

While the conventional boiler heats and stores water in a tank before use, it does not provide the same level of energy efficiency since it continuously maintains the water temperature, even when hot water isn't needed. The heat exchanger serves a different purpose, transferring heat from one medium to another but does not itself produce and supply hot water. Thus, the instantaneous boiler stands out for its ability to deliver hot water only as necessary, which aligns with the growing emphasis on energy conservation and efficient resource usage in modern HVACR practices.