HRSG manufacturers typically recommend against chemically cleaning new units prior to operation. Experience from a reliability and water chemistry standpoint has shown that this may not be a wise alternative. This paper discusses some of the concerns associated with not chemically cleaning new units prior to operation, along with the impact on reliability associated with some design considerations.

Key words: HRSG, pearlite, ferrite, spheroidization, duct firing, maricite, acid phosphate corrosion, hydrogen damage, caustic attack, Widmanstatten structure.