Abstract: A heat exchanger takes the form of a cylindrical tank having an inlet at one end to receive an influent liquid to be chilled, an outlet at the opposite end of the tank from which the chilled liquid may be discharged. A cooling coil is wrapped around the outer side wall of the tank for circulating a refrigerant in conductive, heat exchange relation to the tank. A cylindrical cup-shaped baffle is arranged coaxially within the tank for directing the influent liquid toward the side wall of the tank, and a pressure-expanded, helically wound conduit is positioned between and disposed in intimate heat exchange contact with both the side wall of the tank and the cup-shaped baffle and defines two relatively separated passages through which separate portions of the influent liquid pass to be chilled by contact with the tank, the baffle and the intervening helically wound conduit.