Refrigerator and control method thereof

A control method of a refrigerator comprising:

• starting an operation of a compressor to supply a refrigerant to an evaporator and a refrigerant pipe in contact with an ice-making tray, where the refrigerant pipe is configured to cool the ice-making tray;
• starting an operation of a first defrost heater provided in a vicinity of the evaporator to remove frost from the evaporator in response to stopping the operation of the compressor;
• stopping the operation of the first defrost heater;
• in response to the stopping of the operation of the first defrost heater, starting a predetermined first timer;
• elapsing the predetermined first timer;
• starting an operation of a second defrost heater provided in contact with the ice-making tray and in a vicinity of the refrigerant pipe to remove frost from the refrigerant pipe, in response to the elapse of the predetermined first timer, wherein heat generated by the second defrost heater is conducted to the ice-making tray and the refrigerant pipe;
• stopping the operation of the second defrost heater only when both (i) a temperature of the ice-making tray or the refrigerant pipe is equal to or greater than a second reference temperature and (ii) a predetermined minimum defrosting time has elapsed since starting the operation of the second defrost heater;
• starting the operation of the compressor after stopping the operation of the second defrost heater;
• and
• controlling a switching valve to allow the refrigerant to be supplied to the refrigerant pipe during the operation of the compressor, which the switching valve is provided in the refrigerant pipe.

A refrigerator comprising:

• an evaporator;
• a first defrost heater provided in a vicinity of the evaporator;
• a refrigerant pipe provided in contact with an ice-making tray;
• a switching valve provided in the refrigerant pipe;
• a second defrost heater provided in contact with the ice-making tray and in a vicinity of the refrigerant pipe such that heat generated by the second defrost heater is conducted to the ice-making tray and the refrigerant pipe;
• a compressor configured to supply a refrigerant to at least one of the evaporator or the refrigerant pipe;
• and
• a processor configured to:
• start an operation of the first defrost heater to heat the evaporator;
• stop the operation of the first defrost heater;
• in response to the stopping of the operation of the first defrost heater, start a predetermined first timer;
• elapse the predetermined first timer;
• start an operation of the second defrost heater to heat the refrigerant pipe, in response to the elapse of the predetermined timer;
• stop the operation of the second defrost heater after stopping the operation of the first defrost heater and only when both (i) a temperature of the ice-making tray or the refrigerant pipe is equal to or greater than a second reference temperature and (ii) a predetermined minimum defrosting time has elapsed since starting the operation of the second defrost heater;
• start an operation of the compressor after stopping the operation of the second defrost heater;
• and
• control the switching valve to allow the refrigerant to be supplied to the refrigerant pipe during the operation of the compressor.