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Knowledge document #3546
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The FRITZ!DECT radiator control's limescale protection function

The radiator control, for example FRITZ!DECT 301, has a limescale protection function that prevents the build-up of limescale in the radiator valve. The limescale protection function is automatically run on Fridays around 11:00 a.m. The valve is completely opened and closed once and then returned to its original position. This function cannot be configured, it is always run even during "vacation switching" and "heat off" times.