Abstract: This paper is aimed at coal-fired power sta-tion boilers with the problem of scrambling for air often oc-curred in the axial in-duced draft fan which is existing be-tween the fans connected in parallel operation, due to the factors such as system reform.Through the overall system analysis of the production site, optimizing the air preheater soot program,leveling ammonia injection grid, and other measures, reduce the resistance of the flue system,we have completely solved the "stubborn disease" in production.The successful experience and scientific practice has a good sig-nificance to generalization and reference.

Key words: Suction fan, Scrambling for air, Cause analysis, Treatment