The instant water heater has an inlet pipe for cold water, which passes through the resistance, heats up, and exits through the hot water outlet pipe. A necessary condition for the instant water heater to initially operate is that the pressure of the incoming cold water is not too low.
The water temperature is regulated by a thermostat, so it does not exceed a maximum value. The temperatures that the hot water reaches are preset so that one can use the hot water directly, without needing to mix it with cold water.
The maximum temperature that can be reached for hot water production is 55 °C, while the maximum water flow rate reaches up to 9.4 liters per minute. Indicatively, 38-42 °C degrees are standard for shower use.