The built-in thermostat is tailored to meet the requirements of various heating systems. It offers several functions that optimize energy resource management: The optimum start function allows the thermostat to autonomously save heating energy by "learning" how much lead time is needed to reach the desired temperature at the set time. This prevents unnecessary and costly preheating. If residents are away for several days, the temperature can be lowered during this time and, with the vacation function, raised back to a comfortable room climate just in time for their return. To do this, only the start and end dates of the vacation need to be entered. However, if someone is only away for a few hours, the temperature can be adjusted to meet specific needs using the party short-term timer, without requiring any changes to the program.