Abstract: An indicator generating method for generating an indicator which is suitable for maintenance prediction of a water heating system is proposed. A power state indication device generates a high power consumption signal if a heating device of the water heating system is activated. The time duration of the activation is such an indicator, if no water flow is present. Furthermore, the time interval between subsequent activations is such an indicator. A predictive maintenance method processes these condition-based indicators and determines a remaining useful lifetime according to a predictive maintenance model. The predictive maintenance device outputs a maintenance signal indicating required maintenance, if the remaining useful lifetime drops below a predetermined threshold. The methods may be performed by water heating systems or beverage makers.

Abstract: An indicator generating method for generating an indicator which is suitable for maintenance prediction of a water heating system is proposed. A power state indication device generates a high power consumption signal if a heating device of the water heating system is activated. The time duration of the activation is such an indicator, if no water flow is present. Furthermore, the time interval between subsequent activations is such an indicator. A predictive maintenance method processes these condition-based indicators and determines a remaining useful lifetime according to a predictive maintenance model. The predictive maintenance device outputs a maintenance signal indicating required maintenance, if the remaining useful lifetime drops below a predetermined threshold. The methods may be performed by water heating systems or beverage makers.