- Electric fan capable of generating a pressure differential between a first zone, named upper pressure zone , and a second zone, named lower pressure zone , the pressure of said upper pressure zone being greater than the pressure of said lower pressure zone , said fan comprising: - a stator ; - a ventilation rotor rotationally mounted relative to the stator , said ventilation rotor being capable of generating a pressure differential between the upper pressure zone and the lower pressure zone ; - a drive device for driving the ventilation rotor , said device comprising: • an electric motor adapted to be able to rotate the ventilation rotor relative to the stator ; • a casing having a wall delimiting an internal space of the casing , said casing being disposed in said upper pressure zone ; • an electronic device, said electronic device being disposed in said internal space of the casing , wherein the stator comprises a chassis supporting the ventilation rotor and the drive device and comprising: - a main support disposed in the lower pressure zone ; - at least one arm rigidly connected to the casing and the main support , wherein each arm comprises at least one duct, named aeration duct , outside the casing and comprising at least: - one opening, named first opening, disposed in the upper pressure zone in the vicinity of an outer face of the wall of said casing ; - one opening, named second opening, disposed in the lower pressure zone ; and, - an opening, named air inlet opening , emerging into the upper pressure zone , characterised in that it comprises at least one air guide mounted on an outer face of the wall of the casing , said air guide forming, with the casing , a passage along part of the outer face of the wall of said casing between a first opening at a first end of the air guide and a second opening at a second end of the air guide, said second opening being disposed facing the air inlet opening of an arm comprising an aeration duct ; and, said air guide being arranged to guide an air flow along a portion of the outer face of the wall of the casing up to the second opening of the air guide . - a stator ; - a ventilation rotor rotationally mounted relative to the stator , said ventilation rotor being capable of generating a pressure differential between the upper pressure zone and the lower pressure zone ; - a drive device for driving the ventilation rotor , said device comprising: • an electric motor adapted to be able to rotate the ventilation rotor relative to the stator ; • a casing having a wall delimiting an internal space of the casing , said casing being disposed in said upper pressure zone ; • an electronic device, said electronic device being disposed in said internal space of the casing , • an electric motor adapted to be able to rotate the ventilation rotor relative to the stator ; • a casing having a wall delimiting an internal space of the casing , said casing being disposed in said upper pressure zone ; • an electronic device, said electronic device being disposed in said internal space of the casing , - a main support disposed in the lower pressure zone ; - at least one arm rigidly connected to the casing and the main support , - one opening, named first opening, disposed in the upper pressure zone in the vicinity of an outer face of the wall of said casing ; - one opening, named second opening, disposed in the lower pressure zone ; and, - an opening, named air inlet opening , emerging into the upper pressure zone , <EOS>