In a printing apparatus a print bar assembly is provided with multiple print bars, a designed space being present between the print bars and a recording medium. A climate control has a feed channel running parallel to a length of the recording medium. Openings lead from the feed channel to the print bars to introduce a conditioned gas flow of predetermined temperature and moisture to the print bars such that a laminar gas flow is generated in the designed space between nozzle plates of the print bars and the recording medium. A barrier is arranged at an intake of the print bar assembly which blocks an air boundary layer entrained with the moving recording medium before the print bar assembly.