path 16 in the embodiment shown in fig2 the condensate formed is discharged into the condensate discharge region 24 u2032 via the condensate discharge line 22 here the condensate discharge region 24 u2032 is located upstream of the compressor 6 in the fresh air flow direction 9 according to fig3 the condensate can also be discharged into the atmosphere consequently the condensate discharge region 24 u2033 is the atmosphere or the environment wherein in this case the condensate must be discharged against the atmospheric ambient pressure or against the regular pressure p 0 as a consequence of this the pressure p 2 must be greater than the ambient pressure p 0 so that the condensate can be discharged into the condensate discharge region 24 u2033 in this case it must be considered that the condensate should if necessary be diluted or neutralized due to its aggressiveness and corrosiveness a condensate discharge device 20 shown in fig4 is arranged downstream of the heat exchanger 10 in the fresh air flow direction 9 here the heat exchanger 10 is preferably tilted such that condensate that is potentially formed in the heat exchanger 10 can flow in a simple manner to the condensate discharge device 20 consequently the condensate discharge device 20 is preferably arranged at the lowest point with respect to the fresh air.