The aim of decarbonizing the heat supply of residential buildings requires among other things a more efficient domestic hot water supply to reduce final energy consumption. At the same time, certain operating parameters (temperatures, retention times) must be ensured to satisfy comfort and hygiene requirements, primarily to prevent legionella.

A system consisting of a central heating storage tank and a central water heater can reach hygiene requirements and improve the efficiency and flexibility of the heat supply, regardless of the heat generator/source. A temperature maintenance band can maintain the required temperature in the domestic hot water installation. By using this self-regulating electric heating system to compensate for heat losses, low return temperatures from the central water heater are possible. Additionally, monitoring this system allows data to be collected from the distribution pipe without the need for additional sensors.

This paper presents a method of optimizing the domestic hot water heating for a residential building by using data from a temperature maintenance band. Firstly, the process of preparing the measured data (electrical variables) for further use (thermal variables) is presented. Then, an algorithm is introduced which uses this data to analyze usage profiles and ensure hygienic operations and reduce energy consumption.