Abstract: A deaerated feedwater supply system for a boiler system includes a water supply conduit configured to provide a supply of water to a deaerator tank and a deaerated makeup water conduit configured to convey deaerated makeup water from the deaerator tank to a surge tank at an elevation in the surge tank below the surface of deaerated feedwater contained therein. A heat exchanger is provided for exchanging heat from deaerated makeup water in the deaerated makeup water conduit to the water in the water supply conduit so that the water is heated prior to entering the deaerator tank and the deaerated makeup water is cooled upon entry into the surge tank. Polypropylene spheres are provided within the surge tank for reducing oxygen absorption into deaerated feedwater. A deaerated feedwater conduit is configured to convey deaerated feedwater from the surge tank to the boiler.