This paper introduced the heating surface purging process during the installation of the supercritical once-through boiler in Huaneng Dongfang Power Plant. The comparison of pipe-blowing date and effect between same type units was investigated. The result shows that the heating surface pre-purge during the installation process is worth popularizing, because it can significantly reduce the boiler’s ignition time and pipe-blowing time, as well as save fuel, desalting water, electricity, the way is worth promotion.