Abstract: A steam generator feed water heater comprises a pressurized enclosure inside which is a heat exchanger through which the feed water is caused to flow. There is at least one horizontal condensate inlet tube, as well as at least one condensate outlet tube at a low point on the enclosure. A double screen device associated with the condensate inlet tube comprises an inner screen with a cylindrical side wall and, surrounding this inner screen, an outer screen having one end linked to the inner screen. A bottom wall common to both screens constitutes an impact wall facing the inner screen. Passage areas are provided by perforations in the screens not facing each other over most of the perimeter of their transverse cross-sections.