An air conditioner system comprising: a plurality of air-conditioners (1 to n); a management server configured to receive air-conditioner data from the plurality of air-conditioners at a predetermined time interval and to analyze the received air-conditioner data to diagnose a state of the air-conditioners, wherein the management server has a memory; and a database configured to store the air-conditioner data therein, wherein the management server is configured to receive the air-conditioner data from the air-conditioners, to store the received air-conditioner data in the memory, and, thereafter, to analyze the air-conditioner data to diagnose the state of the air-conditioners, and wherein the management server is configured to determine, based on a diagnostic result, whether the air-conditioner data corresponds to a normal, abnormal or failure state, wherein the management server includes: a communication unit for receiving the air-conditioner data; a main control unit for storing the air-conditioner data in the memory; a diagnosing unit for analyzing the air-conditioner data to determine whether the air-conditioner data corresponds to a normal, abnormal, or failure state; and a filtering unit for filtering air-conditioner data, wherein the filtering unit is configured to determine whether the air-conditioner data is readable data, and to discard the data when the data is not readable data, the air conditioning system being characterized in that when the main control unit determines, based on the diagnosis result, that the air-conditioner data corresponds to the normal state, the main control unit is configured to delete the air-conditioner data from the memory and discard the air-conditioner data, and in that when the main control unit determines, based on the diagnosis result, that the air-conditioner data corresponds to the abnormal or failure state, the main control unit is configured to store the air-conditioner data into the database. a plurality of air-conditioners (1 to n); a management server configured to receive air-conditioner data from the plurality of air-conditioners at a predetermined time interval and to analyze the received air-conditioner data to diagnose a state of the air-conditioners, wherein the management server has a memory; and a database configured to store the air-conditioner data therein, wherein the management server is configured to receive the air-conditioner data from the air-conditioners, to store the received air-conditioner data in the memory, and, thereafter, to analyze the air-conditioner data to diagnose the state of the air-conditioners, and wherein the management server is configured to determine, based on a diagnostic result, whether the air-conditioner data corresponds to a normal, abnormal or failure state, wherein the management server includes: a communication unit for receiving the air-conditioner data; a main control unit for storing the air-conditioner data in the memory; a diagnosing unit for analyzing the air-conditioner data to determine whether the air-conditioner data corresponds to a normal, abnormal, or failure state; and a filtering unit for filtering air-conditioner data, wherein the filtering unit is configured to determine whether the air-conditioner data is readable data, and to discard the data when the data is not readable data, the air conditioning system being characterized in that when the main control unit determines, based on the diagnosis result, that the air-conditioner data corresponds to the normal state, the main control unit is configured to delete the air-conditioner data from the memory and discard the air-conditioner data, and in that when the main control unit determines, based on the diagnosis result, that the air-conditioner data corresponds to the abnormal or failure state, the main control unit is configured to store the air-conditioner data into the database. a communication unit for receiving the air-conditioner data; a main control unit for storing the air-conditioner data in the memory; a diagnosing unit for analyzing the air-conditioner data to determine whether the air-conditioner data corresponds to a normal, abnormal, or failure state; and a filtering unit for filtering air-conditioner data, wherein the filtering unit is configured to determine whether the air-conditioner data is readable data, and to discard the data when the data is not readable data, the air conditioning system being characterized in that when the main control unit determines, based on the diagnosis result, that the air-conditioner data corresponds to the normal state, the main control unit is configured to delete the air-conditioner data from the memory and discard the air-conditioner data, and in that when the main control unit determines, based on the diagnosis result, that the air-conditioner data corresponds to the abnormal or failure state, the main control unit is configured to store the air-conditioner data into the database.