PURPOSE: To improve the heat transmission performance per unit or cost by downwardly spraying uniform temperature evaporative liquid across an indirect evaporative heat exchange section containing liquid stream, spraying the evaporative liquid across a direct evaporative heat exchange section and respraying the collected liquid into the indirect evaporative heat exchange section.

CONSTITUTION: An uniform temperature evaporative liquid is downwardly sprayed into an indirect evaporative heat exchange section 50 to indirectly exchange sensible heat with a hot fluid stream flowing within a series of enclosed circuits. After the evaporative fluid descends through the entire indirect evaporative heat exchange section 50 and absorbs heat, it is distributed across fill media within the direct evaporative heat exchange section 90 for cooling. Separate ambient streams are simultaneously drawn into each of the heat exchange sections to evaporatively cool the evaporative liquid flowing within each section. The water cooled in the direct evaporative heat exchange section 90 is then collected in a sump 36 where as the water descends, it indirectly exchanges sensible heat with the fluid from circuit to circuit of the indirect evaporative heat exchange section 50.