Refrigerator and server device capable of diagnosing state and methods thereof

A refrigerator comprising:

• a plurality of sensors;
• memory storing instructions;
• and
• at least one processor,
• wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to:
• acquire state information of the refrigerator based on sensing values of the plurality of sensors,
• calculate a frost formation index value for frost formation or a dew formation index value for dew formation of the refrigerator based on the state information,
• store the index value in the memory, and
• diagnose a frost formation state or a dew formation state based on index values cumulatively stored during a predetermined period of time.

A method for diagnosing a state of a server device, the method comprising:

• acquiring and storing state information of at least one refrigerator;
• calculating and storing a frost formation index value for frost formation or a dew formation index value for dew formation in the at least one refrigerator based on the stored state information;
• and
• diagnosing a degree of frost formation or a degree of dew formation based on index values cumulatively stored during a predetermined period of time.