Refrigerating and air-conditioning apparatus

Abstract

A refrigerating and air-conditioning apparatus that achieves reduced limitations with respect to the communication of indoor units and can identify which indoor unit is connected to each branch port is obtained. Indoor units are made to operate on a one-by-one basis, and it is identified which indoor unit is connected to each branch port on the basis of the difference between an inlet temperature and an outlet temperature at the branch port at that time.

1 . A refrigerating and air-conditioning apparatus comprising:
 a refrigeration cycle that makes a refrigerant circulate therethrough by connecting a compressor, a heat-source-side heat exchanger, at least one expansion valve, and at least one intermediate heat exchanger; and   a heat-medium circuit that makes a heat medium circulate therethrough by connecting at least one pump, a plurality of use-side heat exchangers, and the intermediate heat exchanger,   wherein the at least one intermediate heat exchanger and the at least one pump are accommodated in a relay unit,   wherein the plurality of use-side heat exchangers are accommodated in respective indoor units,   wherein each indoor unit includes an indoor-unit controller that performs on-off control for operation performed by the use-side heat exchanger for exchanging heat between the heat medium and a thermal load,   wherein the relay unit includes   a plurality of branch ports that are connected to the plurality of use-side heat exchangers and make the heat medium circulate to the use-side heat exchangers,   outlet temperature sensors that are provided for the respective branch ports and each detect an outlet temperature of the heat medium flowing out of the branch port to the corresponding use-side heat exchanger,   inlet temperature sensors that are provided for the respective branch ports and each detect an inlet temperature of the heat medium flowing into the branch port from the corresponding use-side heat exchanger, and   a relay-unit controller that is connected to the indoor-unit controllers by a transmission line and controls operation of each indoor-unit by transmitting an operation command or a stop command thereto via the transmission line, and   wherein the relay-unit controller makes the indoor units operate on a one-by-one basis and identifies which of the indoor units is connected to each branch port on the basis of a difference between the inlet temperature and the outlet temperature at the branch port.   
     
     
         2 . The refrigerating and air-conditioning apparatus of  claim 1 ,
 wherein, in a state where the heat medium heated or cooled by performing a heating only operation mode, in which the heat medium is heated by causing a high-temperature high-pressure refrigerant discharged from the compressor to flow to the intermediate heat exchanger, or a cooling only operation mode, in which the heat medium is cooled by causing a low-temperature low-pressure refrigerant to flow to the intermediate heat exchanger, circulates to the plurality of use-side heat exchangers,
 the relay-unit controller 
 makes each indoor unit operate on a one-by-one basis, acquires the inlet temperature and the outlet temperature at each branch port, and 
 identifies that the operating indoor unit is connected to the branch port at which the difference between the inlet temperature and the outlet temperature is larger than a predetermined value. 
   
     
     
         3 . The refrigerating and air-conditioning apparatus of  claim 1 ,
 wherein, in a state where the heat medium heated or cooled by performing a heating only operation mode, in which the heat medium is heated by causing a high-temperature high-pressure refrigerant discharged from the compressor to flow to the intermediate heat exchanger, or a cooling only operation mode, in which the heat medium is cooled by causing a low-temperature low-pressure refrigerant to flow to the intermediate heat exchanger, circulates to the plurality of use-side heat exchangers, the relay-unit controller
 makes each indoor unit operate on a one-by-one basis, acquires the inlet temperature and the outlet temperature at each branch port, and 
 determines there is a setting error if at none of the branch ports the difference between the inlet temperature and the outlet temperature is larger than a predetermined value. 
   
     
     
         4 . The refrigerating and air-conditioning apparatus of  claim 1 ,
 wherein the relay-unit controller transmits a binary signal corresponding to the operation command and the stop command via the transmission line, and   wherein each indoor-unit controller performs on-off control for the operation of the indoor unit in accordance with the binary signal received via the transmission line.   
     
     
         5 . The refrigerating and air-conditioning apparatus of  claim 1 ,
 wherein only a binary signal is transmitted via the transmission line.