Method and device for controlling air conditioner and air conditioner

The invention relates to the technical field of air conditioner control, and discloses a method for controlling an air conditioner, which comprises the following steps: acquiring the fault duration of a fan under the condition that the fan of the air conditioner is restarted after a locked-rotor fault is determined; under the condition that the fault duration is lower than a set fault threshold value and the air conditioner is in a refrigeration mode, the air conditioner is controlled to close the refrigeration mode and start a dehumidification mode; under the condition that it is determined that the fan operates stably, the target output load of the fan is determined; and controlling the fan according to the target output load. According to the scheme, the target output load conforming to the current temperature and humidity condition can be determined under the condition that the air conditioner fan is restarted after the locked-rotor fault exists, so that under the condition that the fan is controlled acco