A method for ventilation of a space with room air by means of a ventilation device disposed in a ceiling of the space, which space is bounded by the ceiling, a floor and a number of wall-like elements with surfaces (D, E; F; G) facing in towards the space, one of which surfaces, called the cooling surface, has a surface temperature which is lower than surface temperatures of the other surfaces, called wall surfaces (E; F; G), which ventilation device comprises a receiving means adjacent to an intake air element, at least one first battery comprising one first throughflow area comprising a heating circuit, a second throughflow area comprising a cooling circuit, a directing means and one first pipe section and one second pipe section which extend through the at least one first battery at two different levels relative to the ceiling or floor, and run through the at least one first battery parallel with one another, which method comprises the steps of: - causing a first air flow, called intake air, to flow through the receiving means into the ventilation device; - causing a second air flow, called recirculating room air, to flow into the ventilation device through the first throughflow area -, thereby being heated by the heating circuit, and flowing through the second throughflow area, thereby being cooled by the cooling circuit or being unaffected if the cooling circuit is inactive; - causing a third air flow, called output air, to flow out from the ventilation device into the space in at least one first output air direction and at least one second output air direction; - mixing heated recirculating room air and intake air with one another to obtain a temperature which is higher than the room air in the space to provide the output air in the first output air direction; - mixing cooled recirculated room air and intake air with one another inside the ventilation device to obtain a temperature which is lower than the room air in the space for providing the output air flowing out from the ventilation device in the second output air direction; - the outflow in the first output air direction entails causing output air to flow out towards the cooling surface, - the outflow in the second output air direction entails causing output air to flow out towards at least one of the other wall surfaces (E; F; G); - leading at least one first medium through the at least one first battery at at least one first temperature for temperature exchange with room air flowing through the at least one first battery; and - regulating the flow in each of the pipe sections (12a, 12b) to either shut off flow through a pipe section or open up flow through a pipe section. - causing a first air flow, called intake air, to flow through the receiving means into the ventilation device; - causing a second air flow, called recirculating room air, to flow into the ventilation device through the first throughflow area -, thereby being heated by the heating circuit, and flowing through the second throughflow area, thereby being cooled by the cooling circuit or being unaffected if the cooling circuit is inactive; - causing a third air flow, called output air, to flow out from the ventilation device into the space in at least one first output air direction and at least one second output air direction; - mixing heated recirculating room air and intake air with one another to obtain a temperature which is higher than the room air in the space to provide the output air in the first output air direction; - mixing cooled recirculated room air and intake air with one another inside the ventilation device to obtain a temperature which is lower than the room air in the space for providing the output air flowing out from the ventilation device in the second output air direction; - the outflow in the first output air direction entails causing output air to flow out towards the cooling surface, - the outflow in the second output air direction entails causing output air to flow out towards at least one of the other wall surfaces (E; F; G); - leading at least one first medium through the at least one first battery at at least one first temperature for temperature exchange with room air flowing through the at least one first battery; and - regulating the flow in each of the pipe sections (12a, 12b) to either shut off flow through a pipe section or open up flow through a pipe section.