A control-cabinet system has a base module and at least one functional module. The base module has a base housing with a first housing face and a second housing face. The functional module has a functional housing with a housing underside, where a circulation channel is arranged. Air flow may be circulated in the circulation channel, where each base connection element comprises circulation openings which are fluidically connected to the circulation channel. The functional connection element comprises coupling openings fluidically connected to an interior of the functional housing. The coupling openings are coupleable to the circulation openings, in which a fluidic connection exists between the circulation channel and the interior of the functional housing. A fluidically closed circulation circuit comprising the circulation channel and the interior of the functional housing is formed, in which air flow may be circulated.