Air-conditioning apparatus and method for installing air-conditioning apparatus

Abstract

An air-conditioning apparatus includes: an outdoor unit including a compressor, and an outdoor heat exchanger; a first indoor unit including a first indoor heat exchanger; a relay unit including a relay heat exchanger through which the refrigerant exchanges heat with a heat medium different from the refrigerant, and a pump; and a second indoor unit including a second indoor heat exchanger, wherein the first indoor unit is installed in a first air-conditioned space, the second indoor unit is installed in a second air-conditioned space, the first air-conditioned space has a volume such that a concentration of the refrigerant in the first air-conditioned space is lower than a reference value even when a total amount of the refrigerant filled in the refrigerant circuit leaks in the first air-conditioned space, and a volume of the second air-conditioned space is smaller than the volume of the first air-conditioned space.

1 . An air-conditioning apparatus comprising:
 an outdoor unit including a compressor configured to cause refrigerant to circulate in a refrigerant circuit, and an outdoor heat exchanger through which the refrigerant flows;   a first indoor unit including a first indoor heat exchanger through which the refrigerant flows;   a relay unit including a relay heat exchanger through which the refrigerant exchanges heat with a heat medium different from the refrigerant, and a pump configured to cause the heat medium to circulate in a heat medium circuit; and   a second indoor unit including a second indoor heat exchanger through which the heat medium flows, wherein   the first indoor unit is installed in a first air-conditioned space,   the second indoor unit is installed in a second air-conditioned space,   the first air-conditioned space has a volume such that a concentration of the refrigerant in the first air-conditioned space is lower than a reference value even when a total amount of the refrigerant filled in the refrigerant circuit leaks in the first air-conditioned space,   a volume of the second air-conditioned space is smaller than the volume of the first air-conditioned space, and   the relay unit and the second indoor unit are installed such that a distance from the relay unit to the second indoor unit is shorter than a distance from the outdoor unit to the first indoor unit.   
     
     
         2 . The air-conditioning apparatus of  claim 1 , wherein the second air-conditioned space has a volume such that a concentration of the refrigerant in the second air-conditioned space is equal to or higher than the reference value when the total amount of the refrigerant filled in the refrigerant circuit leaks in the second air-conditioned space. 
     
     
         3 . The air-conditioning apparatus of  claim 1 , wherein the reference value is equal to or smaller than a value of lower flammability limit of the refrigerant. 
     
     
         4 . The air-conditioning apparatus of  claim 1 , wherein
 the second indoor unit includes a flow control valve connected to the second indoor heat exchanger, and   an amount of the heat medium flowing to the second indoor heat exchanger is controlled by the flow control valve.   
     
     
         5 . The air-conditioning apparatus of  claim 1 , wherein an amount of the heat medium flowing to the second indoor heat exchanger is controlled by the pump. 
     
     
         6 . The air-conditioning apparatus of  claim 1 , wherein
 the air-conditioning apparatus comprises two of the relay units,   the second indoor unit is connected to each of the two relay units, and   the two relay units operate individually in response to an operating condition of the second indoor unit connected thereto.   
     
     
         7 . The air-conditioning apparatus of  claim 1 , wherein the relay unit is installed such that a distance from the outdoor unit to the relay unit is shorter than a distance from the outdoor unit to the first indoor unit. 
     
     
         8 . The air-conditioning apparatus of  claim 1 , wherein the refrigerant has flammability or toxicity, while the heat medium does not have the flammability or the toxicity. 
     
     
         9 . A method for installing an air-conditioning apparatus, the air-conditioning apparatus including
 an outdoor unit including a compressor configured to cause refrigerant to circulate in a refrigerant circuit, and an outdoor heat exchanger through which the refrigerant flows,   a first indoor unit including a first indoor heat exchanger through which the refrigerant flows,   a relay unit including a relay heat exchanger through which the refrigerant exchanges heat with a heat medium different from the refrigerant, and a pump configured to cause the heat medium to circulate in a heat medium circuit, and   a second indoor unit including a second indoor heat exchanger through which the heat medium flows, the method comprising:   determining, for a volume of each of a plurality of air-conditioned spaces, whether or not a concentration of the refrigerant in the each of the plurality of air-conditioned spaces is lower than a reference value when a total amount of the refrigerant filled in the refrigerant circuit leaks in the each of the plurality of air-conditioned spaces;   installing the first indoor unit in one of the plurality of air-conditioned spaces in which the concentration of the refrigerant is lower than the reference value, and installing the second indoor unit in another one of the plurality of air-conditioned spaces in which the concentration of the refrigerant is equal to or higher than the reference value; and   installing the relay unit and the second indoor unit such that a distance from the relay unit to the second indoor unit is shorter than a distance from the outdoor unit to the first indoor unit.   
     
     
         10 . An air-conditioning apparatus comprising:
 an outdoor unit including a compressor configured to cause refrigerant to circulate in a refrigerant circuit, and an outdoor heat exchanger through which the refrigerant flows;   a first indoor unit including a first indoor heat exchanger through which the refrigerant flows;   a relay unit including a relay heat exchanger through which the refrigerant exchanges heat with a heat medium different from the refrigerant, and a pump configured to cause the heat medium to circulate in a heat medium circuit; and   a second indoor unit including a second indoor heat exchanger through which the heat medium flows, wherein   the first indoor unit is installed in a first air-conditioned space,   the second indoor unit is installed in a second air-conditioned space,   the first air-conditioned space has a volume such that a concentration of the refrigerant in the first air-conditioned space is lower than a reference value even when a total amount of the refrigerant filled in the refrigerant circuit leaks in the first air-conditioned space,   a volume of the second air-conditioned space is smaller than the volume of the first air-conditioned space,   the second indoor unit does not include a flow control valve, and   an amount of the heat medium flowing to the second indoor heat exchanger is controlled only by the pump.