The oil-bearing condensate flows into the settling chamber under pressure. This relieves the overpressure without causing turbulences in the next separation tank. Any coarse dirt particles present are retained in a removable collection container. In the separation tank, the oil is deposited on the surface by means of gravity separation and guided to the oil collection container. This pre-cleaned condensate now flows to the filter stage. The pre-filter binds the residual oil drops in its material and the last oil residues are safely and reliably retained in the main filter cartridge. The treated condensate exits the oil/water separator via the water outlet.