How do instantaneous water heaters work and what are their advantages over stored water systems?
The general operating principle is the same for all instantaneous water heaters and is described below. These very compact appliances offer a heating output high enough to heat the incoming cold water as it flows through. There is no need for a DHW cylinder, such as those usually required in centralised DHW systems.
The traditional method of storing heat in a central store (the airing cupboard) loses heat when not in use. In addition when you turn on the tap there are heat losses along the length of the pipe from the store. There are also hygenic considerations because of the potential of the warm water that sits in the pipes in between uses to grow bacteria.
Heating the water instantaneously at point of use solves all these problems.
Depending on the appliance type, these instantaneous water heaters differ in terms of the control concept, equipment level, operation, and heating element technology. All this has an impact on efficiency and DHW convenience.
Did you know? Electronically controlled instantaneous water heaters save up to 30 % on energy and water costs compared to hydraulic instantaneous water heaters.