AIR-CONDITIONING SYSTEM

Provided is an air conditioning system capable of accurately determining the performance of a refrigeration cycle apparatus, regardless of information transmitted from a thermostat connected thereto. The air conditioning system includes an air conditioning apparatus, a connection unit (610), a communication unit (620), and a determination processing unit (640). The air conditioning apparatus performs air conditioning of an air-conditioning target space. The connection unit is connectable to a plurality of types of thermostats. The communication unit performs communication with the thermostat connected to the connection unit. The determination processing unit performs a performance determination process for the refrigeration cycle apparatus. (A) The determination processing unit performs different performance determination processes according to whether a first type of thermostat is connected to the connection unit or whether a second type of thermostat different from the first type of thermostat is connected to the connection unit. Alternatively, (B) the air conditioning apparatus changes a method for using information received by the communication unit from the thermostat according to whether being in a determination processing time over which the performance determination process is performed or in a non-determination processing time over which the performance determination process is not performed.