Abstract: This paper focuses on the serious coking observed on left and front water walls in burner area encountered by a 330 MW boiler in an thermal plant which resulted in poor adaptability to coal quality and seriously affected safe and economic operation of the boiler. In order to explore technical basis and utility of bias correction of boiler thermal dynamics, cold status bias correction experiment was carried out, which verified that adjusting secondary air valve can control to a certain extent the position of strong wind ring under thermal dynamic field. According to that result, practical application of the bias control scheme to thermal dynamics of ther burning boiler was conducted, and was proved to alleviate obviously coking on the left and the front water walls.