A directed freezing precipitation detection device comprising: - at least one sloped thermo-conducting sheet, wherein the at least one sloped thermo conducting sheet is coated with a wide range spectral irradiance sensitive coating for reaching a maximum of the net irradiance due to absorption and emission, - at least one first wetness detection means in thermo-conducting contact with the upper surface of the sloped thermo-conducting sheet, - at least one second wetness detection means in thermo-conducting contact with the lower surface of said sloped thermo-conducting sheet, - at least one surface temperature detection means in thermo-conducting contact with said sloped thermo-conducting sheet, - at least one processor configured to receive at least one first signal (11;11A,11B,11C), wherein the first signal (11;11A,11B,11C) is composed of a differential measurement of wetness from the first wetness detection means and the second wetness detection means, and a measurement of the surface temperature on the thermo-conducting sheet from the surface temperature detection means, to analyse said first signal (11;11A,11B,11C) and determine the presence or the absence of a freezing precipitation and to distinguish between direct and indirect precipitation on the surface of the sloped thermo-conducting sheet, - at least one first apparatus for external power relay adapted for receiving at least a second signal from the processor, said signal being either adapted for permitting to provide power or not to provide power to at least one third apparatus, wherein the third apparatus is a rain gauge or an internal roof drain provided with a heating system, - at least one second apparatus for power supply being connected to said processor and also to said first apparatus, - wherein said second apparatus for power supply is not actively heating said thermo-conducting sheet, - said first apparatus adapted for permitting to provide power to said third apparatus only when a temperature less or equal to a predetermined threshold is detected by said surface temperature detection means and the presence of a directed freezing precipitation is detected by the first and second wetness detection means (1;2). - at least one sloped thermo-conducting sheet, wherein the at least one sloped thermo conducting sheet is coated with a wide range spectral irradiance sensitive coating for reaching a maximum of the net irradiance due to absorption and emission, - at least one first wetness detection means in thermo-conducting contact with the upper surface of the sloped thermo-conducting sheet, - at least one second wetness detection means in thermo-conducting contact with the lower surface of said sloped thermo-conducting sheet, - at least one surface temperature detection means in thermo-conducting contact with said sloped thermo-conducting sheet, - at least one processor configured to receive at least one first signal (11;11A,11B,11C), wherein the first signal (11;11A,11B,11C) is composed of a differential measurement of wetness from the first wetness detection means and the second wetness detection means, and a measurement of the surface temperature on the thermo-conducting sheet from the surface temperature detection means, to analyse said first signal (11;11A,11B,11C) and determine the presence or the absence of a freezing precipitation and to distinguish between direct and indirect precipitation on the surface of the sloped thermo-conducting sheet, - at least one first apparatus for external power relay adapted for receiving at least a second signal from the processor, said signal being either adapted for permitting to provide power or not to provide power to at least one third apparatus, wherein the third apparatus is a rain gauge or an internal roof drain provided with a heating system, - at least one second apparatus for power supply being connected to said processor and also to said first apparatus, - wherein said second apparatus for power supply is not actively heating said thermo-conducting sheet, - said first apparatus adapted for permitting to provide power to said third apparatus only when a temperature less or equal to a predetermined threshold is detected by said surface temperature detection means and the presence of a directed freezing precipitation is detected by the first and second wetness detection means (1;2).