The first part of the book presents the results of a study of the physical processes that determine the operation of convective heating surfaces: heat exchange, contamination of the surface with ash deposits, ash wear of pipes, loss of sulfuric acid dew from flue gases and corrosion of metal pipes . Refined methods of calculating these processes. are recommended The second part of the book presents practical conclusions and recommendations for improving convective surfaces in the direction of reducing their ash pollution , Increased resistance to corrosion , Prevention of wear and tear , Reduction of metal dimensions and costs , Reducing energy consumption by thrust and blow, creating greater opportunities to reduce the temperature of exhaust gases. The book can serve as a manual for engineering and technical workers involved in the operation, as well as the design and reconstruction of existing steam boiler units.