After the coal is added or is reduced, the changing of returns feeder temperature is faster than the changing of fluidization bed temperature, therefore the temperature of returns feeder during normal operation can be regarded as the indication signal for bed temperature adjusting. If the temperature of returns rises， the bed temperature will rise accordingly. If the bed temperature is not stable, during adjusting, it is required to pay close attention to the returns temperature. After the temperature of returns is stable, the bed temperature will be gradually stable. The stabilization of the returns feeder temperature is the effective means for ensuring the stable combustion in circulating fluidized bed boiler. During adjusting, the changing of returns feeder temperature shall keep consistent with that of the circulating fluidized bed boiler and the temperature of the returns feeder shall be slightly higher than the circulating fluidized bed boiler. In order to ensure the safe operation of the boiler, the returns temperature is strictly controlled under 1020℃. When the difference between the returns temperature with the bed temperature is larger than 30℃ or above, the causes shall be identified. If the coal particle size is too fine, when necessary, part of the circular ash may be discharged in order to prevent the returns feeder from ash-blocking.