Air conditioner and refrigerant control method thereof

Abstract

Disclosed are an air conditioner and a refrigerant control method thereof. An air conditioner according to an embodiment of the invention an outdoor unit including a compressor, an outdoor heat exchanger, and a four-way valve that switches a flow passage of refrigerant, an indoor unit including an indoor heat exchanger, an indoor expansion unit disposed at a refrigerant inlet side of the indoor heat exchanger and allowing the refrigerant to be expanded during the cooling operation, an outdoor expansion unit disposed at a refrigerant inlet side of the outdoor heat exchanger and allowing the refrigerant to be expanded during the heating operation, and a control unit controlling the indoor expansion unit and the outdoor expansion unit such that the refrigerant is expanded in the indoor expansion unit during the cooling operation and the refrigerant is expanded in the outdoor expansion unit during the heating operation. Therefore, the distance between the evaporator and the expansion unit is reduced to thereby raise operating efficiency.

1 . An air conditioner comprising:
 an outdoor unit including a compressor, an outdoor heat exchanger, and a four-way valve that switches a flow passage of refrigerant;   an indoor unit including an indoor heat exchanger;   an indoor expansion unit disposed at a refrigerant inlet side of the indoor heat exchanger and allowing the refrigerant to be expanded during the cooling operation;   an outdoor expansion unit disposed at a refrigerant inlet side of the outdoor heat exchanger and allowing the refrigerant to be expanded during the heating operation; and   a control unit controlling the indoor expansion unit and the outdoor expansion unit such that the refrigerant is expanded in the indoor expansion unit during the cooling operation and the refrigerant is expanded in the outdoor expansion unit during the heating operation.   
   
   
       2 . The air conditioner of  claim 1 ,
 wherein the indoor expansion unit includes a first branch channel and a second branch channel that are connected in parallel with the indoor heat exchanger, an indoor capillary tube that is formed in one of the first branch channel and the second branch channel, and a first switching valve that is formed on the other branch channel, and the control unit controls such that the first switching valve is blocked during the cooling operation and the first switching valve is opened during the heating operation.   
   
   
       3 . The air conditioner of  claim 2 ,
 wherein the compressor includes an inverter compressor, the first switching valve includes an indoor electronic expansion valve, and the control unit controls such that the opening of the indoor electronic expansion valve is controlled according to a load amount of the indoor unit during the cooling operation, and the indoor electronic expansion valve is completely opened during the heating operation.   
   
   
       4 . The air conditioner of  claim 2 ,
 wherein the outdoor expansion unit includes a third branch channel and a fourth branch channel that are connected in parallel with the outdoor heat exchanger, an outdoor capillary tube that is formed in one of the third branch channel and the fourth branch channel, and a second switching valve that is formed on the other branch channel, and the control unit controls such that the second switching valve is blocked during the cooling operation and the second switching valve is opened during the heating operation.   
   
   
       5 . The air conditioner of  claim 4 ,
 wherein the compressor includes an inverter compressor, the second switching valve includes an indoor electronic expansion valve, and the control unit controls such that the indoor electronic expansion valve is completely opened during the cooling operation, and the opening of the indoor electronic expansion valve is controlled according to a load amount of the indoor unit.   
   
   
       6 . An air conditioner comprising:
 an outdoor unit including a compressor, and an outdoor heat exchanger; and   an indoor unit including an indoor heat exchanger, a first branch channel and a second branch channel that are formed in parallel at a refrigerant inlet side of the indoor heat exchanger, an indoor capillary tube that is formed on one of the first branch channel and the second branch channel, and a first switching valve that is formed on the other branch channel so as to switch the corresponding branch channel.   
   
   
       7 . The air conditioner of  claim 6 ,
 wherein the compressor includes an inverter compressor, and the first switching valve includes an indoor electronic expansion valve.   
   
   
       8 . The air conditioner of  claim 7 , further comprising:
 a four-way valve disposed at a discharge side of the compressor and switching a flow passage of the refrigerant;   a third branch channel and a fourth branch channel formed in parallel at an inlet side of the outdoor heat exchanger during the heating operation;   an outdoor capillary tube disposed in one of the third branch channel and the fourth branch channel; and   an outdoor electronic expansion valve switching the other branch channel.   
   
   
       9 . The air conditioner of  claim 8 , further comprising:
 a control unit controlling the four-way valve to switch the flow passage of the refrigerant according to an operating mode, controlling the indoor electronic expansion valve to allow the refrigerant to be expanded at the refrigerant inlet side of the indoor heat exchanger, and at the same time, controlling the outdoor electronic expansion valve to be completely opened during the cooling operation, and controlling the outdoor electronic expansion valve to allow the refrigerant to be expanded at the refrigerant inlet side of the outdoor heat exchanger, and at the same time, controlling the indoor electronic expansion valve to be completely opened during the heating operation.   
   
   
       10 . The air conditioner of  claim 7 , further comprising:
 a control unit controlling the indoor electronic expansion valve according to a load amount of the indoor unit during the cooling operation.   
   
   
       11 . The air conditioner of  claim 6 , further comprising:
 a four-way valve disposed at a discharge side of the compressor and switching a flow passage of the refrigerant;   a third branch channel and a fourth branch channel formed in parallel at an inlet side of the outdoor heat exchanger during the heating operation;   an outdoor capillary tube disposed in one of the third branch channel and the fourth branch channel; and   a second switching valve switching the other branch channel.   
   
   
       12 . The air conditioner of  claim 11 , further comprising:
 a control unit controlling the four-way valve to switch the flow passage of the refrigerant according to an operating mode, controlling the first switching valve to allow the refrigerant to be expanded at the refrigerant inlet side of the indoor heat exchanger, and at the same time, controlling the second switching valve to be completely opened during the cooling operation, and controlling the second switching valve to allow the refrigerant to be expanded at the inlet side of the outdoor heat exchanger and at the same time, controlling the first switching valve to be opened during the heating operation.   
   
   
       13 . The air conditioner of  claim 6 , further comprising:
 a control unit controlling the first switching valve to be blocked during the cooling operation.   
   
   
       14 . A refrigerant control method of an air conditioner which has an outdoor unit including a compressor, an outdoor heat exchanger, and a four-way valve that switches a flow passage of refrigerant; an indoor unit including an indoor heat exchanger; an indoor expansion unit disposed at a refrigerant inlet side of the indoor heat exchanger and allowing the refrigerant to be expanded during the cooling operation; and an outdoor expansion unit disposed at a refrigerant inlet side of the outdoor heat exchanger and allowing the refrigerant to be expanded during the heating operation, the method comprising:
 switching the flow passage of the refrigerant according to a selected operating mode; and   controlling the indoor expansion unit and the outdoor expansion unit such that the refrigerant is expanded in the indoor expansion unit during the cooling operation and the refrigerant is expanded in the outdoor expansion unit during the heating operation.   
   
   
       15 . The method of  claim 14 ,
 wherein the indoor expansion unit includes a first branch channel and a second branch channel that are connected in parallel at a refrigerant inlet side of the indoor heat exchanger, an indoor capillary tube that is formed in one of the first branch channel and the second branch channel, and an indoor electronic expansion valve that is formed in the other branch channel,   the outdoor expansion unit includes a third branch channel and a fourth branch channel that are connected in parallel at a refrigerant inlet side of the outdoor heat exchanger, an outdoor capillary tube that is formed in the third branch channel, and an outdoor electronic expansion valve that is formed in the fourth branch channel, and   in the controlling of the indoor expansion unit and the outdoor expansion unit, during the cooling operation, the outdoor electronic expansion valve is completely opened, and the opening of the indoor electronic expansion valve is controlled according to a load amount of the indoor unit, and during the heating operation, the indoor electronic expansion valve is completely opened, and the opening of the outdoor electronic expansion valve is controlled according to a load amount of the indoor unit.