Multi-type air conditioner, indoor unit indoor electronic expansion valve operation confirmation method, computer program, and fault diagnosis apparatus

摘要

Provided are a multi-type air conditioner, a method for checking the operation of indoor-side electronic expansion valves of indoor units, a computer program, and a fault diagnosis system that allow the operation of electronic expansion valves of indoor units to be reliably checked. A saturation temperature (TS) is calculated from a refrigerant pressure (PL) detected on the low-pressure side of an outdoor unit by a pressure sensor, and the operation of electronic expansion valves is checked using temperature differences (TD) between the calculated saturation temperature (TS) and the temperatures (TE) of indoor heat exchangers detected by temperature sensors. This allows the effect of variations in refrigerant pressure (PL) to be canceled so that the operation of the electronic expansion valves is reliably checked.