The climate meter “i-Tronic TFC” assists with the optimisation of a room’s climate. The displayed values serve the user as an indicator for an energy efficient room airing (e.g. shock ventilation) leading to an improved air quality. The temperature, air humidity and carbon dioxide content in the room air are detected by the “i-Tronic TFC”. Furthermore, the minimum and maximum values of the last 24 hours are displayed. To improve reading, the display can be illuminated blue with a key stroke. The stable stand of the “i-Tronic” which allows for a comfortable positioning of the device features two integrated rechargeable batteries offering a high degree of user friendliness and flexibility. The design concept and easy operation are harmonised. Thanks to the reduced form and the colour, the “i-Tronic TFC” does not constitute a foreign object but integrates itself into its surroundings. During development, function, shape and an economical use of material were taken into consideration.