Air-conditioning apparatus

Abstract

An indoor unit includes an air-sending fan, an air inlet through which air of an indoor space is sucked in, and an air outlet located above the air inlet and through which the air sucked in through the air inlet is blown out to the indoor space. A control unit activates the air-sending fan when leakage of the refrigerant is detected. When M [kg] represents an amount of charge of the refrigerant in a refrigeration cycle, LFL [kg/m 3 ] represents a lower flammable limit of the refrigerant, A [m 2 ] represents a floor area of the indoor space, and Ho [m] represents a height of the air outlet above a floor surface of the indoor space, the amount of charge M, the lower flammable limit LFL, the floor area A, and the height Ho satisfy a relationship of M<LFL×A×Ho.

1 . An air-conditioning apparatus comprising:
 a refrigeration cycle through which refrigerant is circulated; and   an indoor unit accommodating at least an indoor heat exchanger of the refrigeration cycle, the indoor unit being disposed in an indoor space   the refrigerant being a flammable refrigerant with a density greater than a density of air under atmospheric pressure,   the indoor unit including an air-sending fan, an air inlet through which air of the indoor space is sucked in, and an air outlet through which the air sucked in through the air inlet is blown out to the indoor space,   the air-conditioning apparatus being configured to dilute leaked refrigerant by operation of the air-sending fan,   when M [kg] represents an amount of charge of the refrigerant in the refrigeration cycle, LFL [kg/m 3 ] represents a lower flammable limit of the refrigerant, A [m 2 ] represents a floor area of the indoor space, and Ho [m] represents a height of the air outlet above a floor surface of the indoor space, the amount of charge M, the lower flammable limit LFL, the floor area A, and the height Ho satisfying a relationship of M<LFL×A×Ho.   
     
     
         2 . An air-conditioning apparatus comprising:
 a refrigeration cycle through which refrigerant is circulated; and   an indoor unit accommodating at least an indoor heat exchanger of the refrigeration cycle, the indoor unit being disposed in an indoor space; and   the refrigerant being a flammable refrigerant with a density greater than a density of air under atmospheric pressure,   the indoor unit including an air-sending fan, an air inlet through which air of the indoor space is sucked in, an air outlet through which the air sucked in through the air inlet is blown out to the indoor space, and a vertical air deflector vane located at the air outlet,   the air-conditioning apparatus being configured to dilute leaked refrigerant by operation of the air-sending fan and to blow out the air upward through the air outlet by the vertical air deflector vane,   when M [kg] represents an amount of charge of the refrigerant in the refrigeration cycle, LFL [kg/m 3 ] represents a lower flammable limit of the refrigerant, A [m 2 ] represents a floor area of the indoor space, Ho [m] represents a height of the air outlet above a floor surface of the indoor space, and Hc [m] represents a height of a ceiling surface above the floor surface of the indoor space, the amount of charge M, the lower flammable limit LFL, the floor area A, the height Ho, and the height Hc satisfying a relationship of LFL×A×Ho≦M<LFL×A×Hc.   
     
     
         3 . (canceled) 
     
     
         4 . The air-conditioning apparatus of  claim 1 , wherein the floor area is a floor area specified by specifications of the air-conditioning apparatus or the indoor unit. 
     
     
         5 . The air-conditioning apparatus of  claim 1 , further comprising a control unit configured to control the indoor unit, wherein the control unit is configured to activate the air-sending fan when leakage of the refrigerant is detected. 
     
     
         6 . The air-conditioning apparatus of  claim 5 , wherein
 the indoor unit includes a refrigerant detection unit, and   the control unit is configured to activate the air-sending fan by a time when concentration of the refrigerant detected by the refrigerant detection unit reaches ¼ of the lower flammable limit.   
     
     
         7 . The air-conditioning apparatus of  claim 1 , wherein
 the indoor unit includes a refrigerant detection unit,   the indoor heat exchanger is connected to an extension pipe via a coupling, and   the refrigerant detection unit is provided in a housing of the indoor unit and below the indoor heat exchanger and the coupling.   
     
     
         8 . The air-conditioning apparatus of  claim 1 , wherein a direction in which the air is blown out through the air outlet is a horizontal direction. 
     
     
         9 . The air-conditioning apparatus of  claim 2 , wherein the floor area is a floor area specified by specifications of the air-conditioning apparatus or the indoor unit. 
     
     
         10 . The air-conditioning apparatus of  claim 2 , further comprising a control unit configured to control the indoor unit, wherein the control unit is configured to activate the air-sending fan and set the vertical air deflector vane to an upward orientation when leakage of the refrigerant is detected. 
     
     
         11 . A refrigerant amount setting method of an air-conditioning apparatus,
 the air-conditioning apparatus including   a refrigeration cycle through which refrigerant is circulated, and   an indoor unit accommodating at least an indoor heat exchanger of the refrigeration cycle, the indoor unit being disposed in an indoor space,   the refrigerant being a flammable refrigerant with a density greater than a density of air under atmospheric pressure,   the indoor unit including an air-sending fan, an air inlet through which air of the indoor space is sucked in, and an air outlet through which the air sucked in through the air inlet is blown out to the indoor space,   the air-conditioning apparatus being configured to dilute leaked refrigerant by operation of the air-sending fan,   the refrigerant amount setting method of the air-conditioning apparatus comprising setting an amount of the refrigerant of the air-conditioning apparatus,   the setting including,   when M [kg] represents an amount of charge of the refrigerant in the refrigeration cycle, LFL [kg/m 3 ] represents a lower flammable limit of the refrigerant, A [m 2 ] represents a floor area of the indoor space, and Ho [m] represents a height of the air outlet above a floor surface of the indoor space, setting the amount of charge M so that the amount of charge M, the lower flammable limit LFL, the floor area A, and the height Ho satisfy a relationship of M<LFL×A×Ho.   
     
     
         12 . The refrigerant amount setting method of an air-conditioning apparatus of  claim 11 , wherein the floor area is a floor area specified by specifications of the air-conditioning apparatus or the indoor unit. 
     
     
         13 . A refrigerant amount setting method of an air-conditioning apparatus,
 the air-conditioning apparatus including   a refrigeration cycle through which refrigerant is circulated, and   an indoor unit accommodating at least an indoor heat exchanger of the refrigeration cycle, the indoor unit being disposed in an indoor space,   the refrigerant being a flammable refrigerant with a density greater than a density of air under atmospheric pressure,   the indoor unit including an air-sending fan, an air inlet through which air of the indoor space is sucked in, an air outlet through which the air sucked in through the air inlet is blown out to the indoor space, and a vertical air deflector vane located at the air outlet,   the air-conditioning apparatus being configured to dilute leaked refrigerant by operation of the air-sending fan and to blow out the air upward through the air outlet by the vertical air deflector vane,   the refrigerant amount setting method of the air-conditioning apparatus comprising setting an amount of the refrigerant of the air-conditioning apparatus,   the setting including,   when M [kg] represents an amount of charge of the refrigerant in the refrigeration cycle, LFL [kg/m 3 ] represents a lower flammable limit of the refrigerant, A [m 2 ] represents a floor area of the indoor space, Ho [m] represents a height of the air outlet above a floor surface of the indoor space, and Hc [m] represents a height of a ceiling surface above the floor surface of the indoor space, setting the amount of charge M so that the amount of charge M, the lower flammable limit LFL, the floor area A, the height Ho, and the height Hc satisfy a relationship of LFL×A×Ho≦M<LFL×A×Hc.   
     
     
         14 . The refrigerant amount setting method of an air-conditioning apparatus of  claim 13 , wherein the floor area is a floor area specified by specifications of the air-conditioning apparatus or the indoor unit.