Room ventilation device has ducts for extraction of stale air and supply of fresh air extending parallel to one another for heat recovery

摘要

The ventilation device is provided as a rectangular casing incorporated in a window opening adjacent one side edge of the window frame, with fans (41,42) for extracting air from the inside of the room and discharging it to the outside and feeding fresh air to the room from the outside via respective air ducts (14,15), extending parallel to one another in a plane parallel to the outside frame of the window, for heat exchange between the extracted air and the fresh air.