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Knowledge document #3546
FRITZ!DECT 302
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The FRITZ!DECT radiator control's limescale protection function

The radiator control, for example FRITZ!DECT 302, has a limescale protection function that prevents the build-up of limescale in the radiator valve. The limescale protection function is automatically triggered 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 executed even during "vacation switching" and "heat off" times.