Systems and methods for detecting a blocked air discharge line of an air compressor are described, which include monitoring motor current (IMTR) drawn by a compressor motor, and calculating a three-point moving average for a steady state current drawn by the compressor motor upon the motor reaching steady state (nominal) operating speed. After expiration of a predetermined time period T1 that commences upon the compressor motor reaching steady state speed, a determination is made regarding whether a difference between a current drawn by the compressor motor and the three-point moving average has exceeded a predetermined current value I2 and is consistent with a current profile indicative of a blocked air line. If a blocked air line is detected, a compressor shut-off command is generated and transmitted to the compressor motor to shut the compressor motor off prior to opening of a safety valve on the compressor.