Feedwater heaters are essential components in power generation systems, particularly within boiler operations. Rugged and durable, these units are designed to pre-heat the feedwater before it enters the boiler, improving the overall efficiency of the power plant. Feedwater heaters in several configurations, including single-zone (condensing only), two-zone (condensing and subcooling), and three-zone (desuperheating, condensing, and subcooling) models. Capable of handling design pressures from atmospheric levels up to 5000 psia, these heaters can be installed either vertically or horizontally based on the system's requirements. Built according to HEI practices and stamped to meet ASME Sec VIII, Div 1 or Div 2 codes, feedwater heaters range in size from compact, table-top units to large models exceeding six feet in diameter. Additionally, the spray water condenser—a specialized single-zone unit—is available for providing hot water for attemperation, which helps regulate the boiling rate within the boiler system. This versatility makes feedwater heaters suitable for a wide array of boiler applications, ensuring optimal performance and longevity.