Air conditioner and a method of controlling an air conditioner

Abstract

An air conditioner and a method of controlling an air conditioner are provided. The air conditioner may include a compressor that compresses a refrigerant and discharges the compressed refrigerant, an outdoor heat exchanger in which outdoor air introduced into an outdoor device and the refrigerant are heat-exchanged with each other, at least one indoor heat exchanger in which indoor air introduced into an indoor device and the refrigerant are heat-exchanged with each other, a plurality of valves respectively disposed in an inflow-side tube and a discharge-side tube of the at least one indoor heat exchanger, and a refrigerant leakage detector that directly or indirectly detects leakage of the refrigerant. When leakage of the refrigerant is detected, the plurality of valves may be blocked or closed in stages.

What is claimed is: 
     
         1 . An air conditioner, comprising:
 a compressor that compresses a refrigerant and discharges the compressed refrigerant;   an outdoor heat exchanger in which outdoor air introduced into an outdoor device and the refrigerant are heat-exchanged with each other;   at least one indoor heat exchanger in which indoor air introduced into an indoor device and the refrigerant are heat-exchanged with each other;   a plurality of valves disposed respectively in an inflow-side tube and a discharge-side tube of the at least one indoor heat exchanger; and   a refrigerant leakage detector that directly or indirectly detects leakage of the refrigerant, wherein when the leakage of the refrigerant is detected, the plurality of valves is blocked in stages.   
     
     
         2 . The air conditioner according to  claim 1 , wherein the plurality of valves comprises:
 a first valve disposed in the inflow-side tube of the indoor heat exchanger; and   a second valve disposed in the discharge-side tube of the indoor heat exchanger, wherein when the leakage of the refrigerant is detected, the first valve is blocked or closed earlier than the second valve.   
     
     
         3 . The air conditioner according to  claim 2 , wherein when the leakage of the refrigerant is detected for a predetermined period of time after the first valve is blocked or closed, the second valve is blocked or closed. 
     
     
         4 . The air conditioner according to  claim 2 , wherein, when the leakage of the refrigerant is not detected for a predetermined period of time (t 2 ) after the first valve is blocked or closed, the first valve is opened, and the second valve is maintained in an open state. 
     
     
         5 . The air conditioner according to  claim 1 , wherein one of the plurality of valves is an outdoor expansion valve or an indoor expansion valve. 
     
     
         6 . The air conditioner according to  claim 1 , wherein the at least one indoor heat exchanger comprises a plurality of indoor heat exchangers, and wherein the air conditioner further comprises a plurality of branch tubes that guides, respectively, the refrigerant into each of the plurality of indoor heat exchangers. 
     
     
         7 . The air conditioner according to  claim 6 , wherein the plurality of branch tubes is disposed between the outdoor heat exchanger and the plurality of indoor heat exchangers, and wherein one of the plurality of valves is disposed in the plurality of branch tubes. 
     
     
         8 . The air conditioner according to  claim 6 , further comprising a counter that detects a number (N) of indoor devices in which the leakage of the refrigerant occurs, and wherein when the number (N) of indoor devices in which the leakage of the refrigerant occurs detected by the counter exceeds a predetermined number (N 1 ), an operation of the outdoor device is stopped. 
     
     
         9 . The air conditioner according to  claim 8 , wherein when the number (N) of indoor devices in which the leakage of the refrigerant occurs exceeds the predetermined number (N 1 ), operations of the compressor and an outdoor device fan are stopped. 
     
     
         10 . An air conditioner, comprising:
 a first valve disposed in a refrigerant suction-side tube of an indoor heat exchanger to selectively block a flow of a refrigerant, with respect to a cooling mode;   a second valve disposed in a refrigerant discharge-side tube of the indoor heat exchanger to selectively block the flow of the refrigerant, with respect to the cooling mode;   a flow switching valve that switches a flow direction of the refrigerant according to an operation mode of the air conditioner;   a refrigerant leakage detector that detects a refrigerant leaking into an indoor space; and   a controller that successively closes the first and second valves when the leakage of the refrigerant is detected by the refrigerant leakage detector.   
     
     
         11 . The air conditioner according to  claim 10 , wherein the controller closes the first valve earlier than the second valve in the cooling mode and closes the second valve earlier than the first valve in a heating mode. 
     
     
         12 . The air conditioner according to  claim 10 , further comprising an indoor device fan that guides a flow of indoor air so that the indoor air passes through the indoor heat exchanger. 
     
     
         13 . The air conditioner according to  claim 12 , wherein the controller enables the indoor device fan to continuously operate while one valve of the first and second valves is blocked or closed. 
     
     
         14 . The air conditioner according to  claim 13 , wherein when both of the first and second valves are blocked or closed, the controller stops an operation of the indoor device fan. 
     
     
         15 . A method of controlling an air conditioner, the method comprising:
 detecting leakage of a refrigerant in an indoor space in which air-conditioning is performed;   closing a first valve disposed in a refrigerant inflow-side tube of an indoor heat exchanger when the leakage of the refrigerant is detected;   thereafter, detecting the leakage of the refrigerant after the first valve is blocked or closed; and   closing a second valve disposed in a refrigerant discharge-side tube of the indoor heat exchanger when the leakage of the refrigerant is detected thereafter.   
     
     
         16 . The method according to  claim 15 , wherein the closing of the valves is performed when a time during which the leakage of the refrigerant is detected exceeds a predetermined reference time. 
     
     
         17 . The method according to  claim 15 , wherein when the leakage of the refrigerant is not detected thereafter, the method further comprises opening the first valve. 
     
     
         18 . The method according to  claim 15 , wherein when the leakage of the refrigerant is first detected, the method further comprises determining whether an operation mode of the air conditioner is a cooling mode or a heating mode, and wherein the first valve disposed in the refrigerant inflow-side tube of the indoor heat exchanger is blocked or closed according to the determined operation mode. 
     
     
         19 . The method according to  claim 15 , wherein when the leakage of the refrigerant is detected thereafter, the method further comprises stopping an operation of an indoor device. 
     
     
         20 . The method according to  claim 15 , wherein when a number (N) of indoor devices in which the leakage of the refrigerant occurs exceeds a predetermined reference number (N 1 ), the method further comprises stopping an operation of an outdoor device.