While a classic water heater heats a large quantity of water, consuming a lot of energy and time, the instant water heater does not have a hot water storage tank and heats only the water that passes through it. Thus, in a short time, you have hot water only when you need it and only for the amount you use at that moment. This makes it an economical solution, while also having a longer lifespan since there is no water tank, and therefore no accumulation of salts on the resistance and other components.
As long as you have the tap open, you will have hot water that is used directly, without mixing with cold water as happens with a classic water heater. Of course, a necessary condition for it to work is that the pressure of the incoming cold water is not too low. In cases of lower inlet temperatures in winter and higher in summer, the performance may vary accordingly.
