Un sistema de ventana de tejado que comprende un conjunto de ventilación con un dispositivo de escape y un método para operar un conjunto de ventilación de dicho sistema de ventana de tejado

In the roof window system, a roof window (1) with a ventilation device (5) is connected to a ventilation assembly (100) comprising an air exhaust device (6) for extracting inside air to the exterior. The ventilation assembly (100) has one or more ventilation units (261, 361) adapted to be connected to the ventilation device (5) of the roof window (1) so as to provide fluid connection between the interior of the building and the exterior, in the mounted condition. The air exhaust device (6) comprises a housing (7) having predefined dimensions and accommodating the ventilation unit or units (261; 361). Each ventilation unit (261, 361) includes a flow channel (263, 363) having a first connecting end (263a, 363a) connected, in a mounted condition, to an inside air inlet (262, 362) in connection with the interior, and a second connecting end (263b, 363b) connected, in the mounted condition, to a through channel (71). The housing (7) comprises the through channel (71) having an ambient air intake end (711) and an air exhaust end (712), the through channel (71) further being connected to the inside air inlet (262, 362) via the flow channel (263, 363) so as to provide the fluid connection between the ventilation device (5) of the roof window (1) and the exterior.