The air conditioner display err indicates that there is something wrong with the air conditioner. Because the specific fault code is not displayed, it is impossible to know exactly what is wrong with the air conditioner. If there is such a fault in the air conditioner at home, first look at the operating instructions of the air conditioner, understand the operation of the air conditioner, and see if it can be restored to normal through the air conditioner remote control. If the problem can't be solved, it is necessary to call special maintenance personnel to check whether the internal wiring of the air conditioner is normal, and return to the factory for maintenance if necessary.