Air-conditioning device

An air-conditioning device, comprising:

• a main circuit in which a compressor, an indoor heat exchanger, a decompressor, and a plurality of parallel heat exchangers connected in parallel are connected by a pipe and in which a refrigerant circulates;
• a flow channel-switching unit connected to the plurality of parallel heat exchangers and configured to select a certain parallel heat exchanger out of the plurality of parallel heat exchangers as a defrosting target for defrosting by melting frost attached to the parallel heat exchanger;
• a bypass pipe configured to cause part of a refrigerant emitted from the compressor to flow into the parallel heat exchanger selected as the defrosting target by the flow channel-switching unit;
• a temperature-detecting unit configured to detect temperatures of the refrigerant in the plurality of parallel heat exchangers;
• and
• at least one processor configured to
• operate the flow channel-switching unit such that an operation mode is switched between a normal heating operation mode in which the plurality of parallel heat exchangers serve as evaporators and a defrosting heating operation mode in which one parallel heat exchanger out of the plurality of parallel heat exchangers is selected as the defrosting target to cause part of the refrigerant to flow thereinto via the bypass pipe and the other parallel heat exchanger out of the plurality of parallel heat exchangers serves as an evaporator;
• and
• sense erroneous installation of an installed component associated with the defrosting based on a magnitude relationship between the detected temperatures in the plurality of parallel heat exchangers detected by the temperature-detecting unit.