Tankless water heater system

Abstract

A tankless water heater system (), with a heat exchanger device () comprising at least one hollow chamber () and at least one electrical heating element (), and a controller device () with a temperature control unit (), a tap event counter unit (), a down-time counter unit () and a time delay unit (); an electrical switching element () for connecting or is connecting one or several heating elements () to/from a power supply; an outlet temperature sensor () linked with the temperature control unit (); a flow rate sensor (); wherein: the tap counter unit () is connected to the flow rate sensor () and is triggered when water flow rate exceeds a tap indication threshold the down-time counter unit () is triggered and retriggered by the tap counter unit () and both provide a down-time event signal after any inactivity period with no water flow and records the duration of inactivity; the time delay unit () is connected to and triggered by the tap counter unit () starting a delay period which duration is switched from a short default delay period to a long delay period by the down-time signal provided by the down-time counter unit (); and the switching elements () are triggered by the time delay unit () only after the delay period has elapsed.