Air conditioning apparatus

Abstract

An air conditioning apparatus includes a pump flow regulating valves that are respectively provided for indoor heat exchangers, heat medium temperature detection units, and a control unit that controls the pump such that a heat medium at a predetermined flow rate circulates through a heat medium circuit, and controls the flow regulating valves such that a flow rate of a heat medium flowing through a largest load indoor heat exchanger becomes equal to a largest heat load target flow rate calculated based on a heat load on the largest heat load indoor heat exchanger and a flow rate of a heat medium flowing through a residual heat load indoor heat exchanger becomes equal to a residual heat load target flow rate calculated based on a heat load on the residual heat load indoor heat exchanger and a temperature of a heat medium flowing into the largest load indoor heat exchanger.

1 . An air conditioning apparatus, comprising:
 a pump that circulates a heat medium in a heat medium circuit;   a plurality of indoor heat exchangers provided in the heat medium circuit and provided in parallel with one another;   a plurality of flow regulating valves respectively provided for the plurality of indoor heat exchangers;   a plurality of heat medium temperature detection units respectively provided for the plurality of indoor heat exchangers;   a heat source device that adjusts a temperature of the heat medium; and   a control unit that: controls the pump such that a heat medium at a predetermined flow rate circulates through the heat medium circuit upon multiple unit operation having the heat medium flowing to the plurality of indoor heat exchangers; regards an indoor heat exchanger of the plurality of indoor heat exchangers as a largest heat load indoor heat exchanger, the indoor heat exchanger having a largest heat load among the plurality of indoor heat exchangers; calculates a largest heat load target flow rate on the basis of a heat load on the largest heat load indoor heat exchanger; controls a flow regulating valve of the plurality of flow regulating valves, the flow regulating valve corresponding to the largest heat load indoor heat exchanger, such that a flow rate of a heat medium flowing through the largest heat load indoor heat exchanger becomes equal to the largest heat load target flow rate; regards another indoor heat exchanger of the plurality of indoor heat exchangers as a residual heat load indoor heat exchanger, the another indoor heat exchanger being different from the largest heat load indoor heat exchanger; and controls another flow regulating valve of the plurality of flow regulating valves, the another flow regulating valve corresponding to the residual heat load indoor heat exchanger, such that a flow rate of a heat medium flowing through the residual heat load indoor heat exchanger becomes equal to a residual heat load target flow rate calculated on the basis of a heat load on the residual heat load indoor heat exchanger and another temperature of a heat medium flowing into the largest heat load indoor heat exchanger, the another temperature having been measured by the heat medium temperature detection unit corresponding to the largest heat load indoor heat exchanger.   
     
     
         2 . The air conditioning apparatus according to  claim 1 , wherein
 the heat source device has a refrigerant circuit including a compressor and a heat medium-refrigerant heat exchanger that causes heat exchange between the heat medium and a refrigerant, and the refrigerant circulates through the refrigerant circuit, and   the control unit
 upon single unit operation having the heat medium flowing through only one indoor heat exchanger of the plurality of indoor heat exchangers, regards the one indoor heat exchanger as a singly operating indoor heat exchanger, controls the pump such that a flow rate of a heat medium flowing to the singly operating indoor heat exchanger becomes equal to a single unit operation target flow rate calculated on the basis of a heat load on the singly operating indoor heat exchanger, and controls the compressor such that a compressor rotational speed of the compressor becomes equal to a single unit operation target compressor rotational speed calculated on the basis of a heat load on the singly operating indoor heat exchanger, and 
 upon the multiple unit operation, controls the compressor such that the compressor rotational speed becomes equal to a multiple unit operation target compressor rotational speed calculated on the basis of a heat load on the largest heat load indoor heat exchanger. 
   
     
     
         3 . The air conditioning apparatus according to  claim 2 , further comprising:
 an outward temperature sensor that measures an outward temperature that is a temperature of a heat medium that has been adjusted in temperature by the heat source device;   a return temperature sensor that measures a return temperature that is a temperature of a heat medium that has flown out from the indoor heat exchangers; and   a storage unit that stores a pump target flow rate table and a flow regulating valve target flow rate table, the pump target flow rate table having a plurality of combinations associated with a plurality of single unit operation target flow rates, the plurality of combinations each being a combination of the outward temperature and a temperature difference between the outward temperature and the return temperature, the flow regulating valve target flow rate table including a plurality of combinations each being a combination of a capacity associated with a temperature of the heat medium and a flow rate, wherein   the control unit
 upon the single unit operation, calculates the single unit operation target flow rate of the plurality of single unit operation target flow rates by referring to the pump target flow rate table, the single unit operation target flow rate corresponding to a combination of: a temperature difference between the outward temperature and the return temperature; and the outward temperature, and 
 upon the multiple unit operation, calculates the residual heat load target flow rate corresponding to a combination of a heat load on the residual heat load indoor heat exchanger and the outward temperature, by referring to the flow regulating valve target flow rate table. 
   
     
     
         4 . The air conditioning apparatus according to  claim 3 , further comprising:
 a plurality of indoor units respectively including the plurality of indoor heat exchangers, wherein   an indoor unit of the plurality of indoor units includes a room temperature sensor that measures a temperature in a room where that the indoor unit has been installed, and   the control unit
 calculates, on the basis of a room temperature measured by the room temperature sensor and a set temperature set on the indoor unit, a heat load on another indoor heat exchanger of the plurality of indoor heat exchangers, the another indoor heat exchanger having been provided in the indoor unit, 
   upon the single unit operation, calculates a single unit operation target outward temperature on the basis of a heat load on the singly operating indoor heat exchanger, and calculates the single unit operation target compressor rotational speed such that the outward temperature becomes equal to the single unit operation target outward temperature, and
 upon the multiple unit operation, calculates a multiple unit operation target outward temperature on the basis of a heat load on the largest heat load indoor heat exchanger, and calculates the multiple unit operation target compressor rotational speed such that the outward temperature becomes equal to the multiple unit operation target outward temperature.