Hello I have seen them in sanitary homes, they are a copy of the Ariston in their temperature control part, which consists of a temperature sensor that sends the data to a central processor and it handles a kind of power control of the resistance of heating. In truth, in theory, it should save energy (since there is no extra energy to heat the water), we will have to wait a while to see what the users are saying, because the truth of all this is seen in the electricity bill. Cheers !