Abstract: A water-steam separator to be used in conjunction with a steam humidifier system used to maintain the relative humidity within a desired range in buildings. The water-separator comprising a body in the form of a closed cylindrical tank with a top end and a bottom end. The water-steam separator also comprises a flow diverter internal to the body which divides the body into a condensate area and an inlet-outlet area; the flow diverter extending substantially from the top end of the body to the bottom end of the body. A partition further divides the inlet-outlet area into a separate outlet area and a separate inlet area. The water-steam separator is fitted with a water drain, a water steam inlet, and a steam outlet.