Patent attributes
A system and method for warmkeeping a steam generator such as a sub-critical steam generator is disclosed. Water extraction piping extracts water from a component of one of the water fill circuits of the sub-critical steam generator. A deaerator heating system having an inventory tank of water mixes the extracted water with the water in the tank, and heats the mix of water to a predetermined temperature level to generate heated deaerated feedwater. Feedwater piping forwards the heated deaerated feedwater at the predetermined temperature level from the deaerator heating system to the water fill circuits of the sub-critical steam generator. The water extraction piping, the deaerator heating system and the feedwater piping operate cooperatively to warmkeep the water fill circuits in accordance with the predetermined temperature level while the sub-critical steam generator is in the unfired stand-by mode of operation.