Focusing on in-service issues like flow-induced vibration, corrosion, and corrosion control, and fouling and fouling control, the book explores performance deterioration in service, maintenance issues, defects, tube failures, and how to detect these issues with NDT methods. It discusses various cleaning processes and repair methods. The book also considers boilers, utility boilers, coal-based thermal power plants, boiler corrosion, and boiler degradation mechanisms. It discusses different types of cooling systems, feedwater treatment, deaerators, feedwater heaters, economizers, condensers, cooling towers, and cooling-water management. The book serves as a useful reference for researchers, graduate students, power plant engineers, and engineers in the field of heat exchanger design, including pressure vessel manufacturers.