Ventilation unit, ventilation system and method for ventilating a building

摘要

A ventilation unit (4) for a building that comprises means (14) for the forced air supply from outside the building via a supply channel (11) to the building and means for forced air extraction (15) from the building via an exhaust channel (12), whereby the supply channel (11) and exhaust channel (12) are linked together to enable heat exchange by means of a heat exchanger (13), characterised in that the ventilation unit (4) is equipped with switching means (19) to selectively switch the forced air supply means (14) on and off, if the forced air extraction means (15) are operating.