Unused High Pressure Feedwater Heater. Manufactured by American Exchanger Services. Size 36-5-312 TEMA Type DEU. Three-zone high-pressure feedwater heater utilizing stainless steel tubes to ASME specification SA-688 type 304 (0.05% max C). Flexitalic Channel Gasket, upgraded nozzles for the 5" and 6" drips inlet to P222 (F22) material, change tube side drain to 1" and use HyTorc style nuts. Serial #4109-01. Built 2020.