Patent ID: 9746222
Date: 2017-08-29
CPC Classifications: F25B

Claim:
1. An air-conditioning apparatus that operates in a heating mode or a cooling mode by sending heated or cooled air into an air-condition space for heating or cooling the space, in which a compressor, a first heat exchanger, an expansion device, and a second heat exchanger are connected by pipes to form a refrigeration cycle, and a non-azeotropic refrigerant mixture is adopted as a refrigerant circulating in the refrigeration cycle, the air-conditioning apparatus comprising: a first temperature detection device disposed on an inlet side of the expansion device, a second temperature detection device disposed on an outlet side of the expansion device; and a controller configured to control operation of the air-conditioning apparatus in the heating mode or the cooling mode based in part on calculating an evaporating temperature Te* and a dew-point temperature Tdew* from a quality Xr of the refrigerant on a downstream side of the expansion device, a temperature glide ΔT determined by a difference between a boiling temperature and a dew-point temperature at a predetermined pressure, and a refrigerant temperature detected by the second temperature detection device, wherein the quality Xr is calculated on a basis of an inlet liquid enthalpy calculated on a basis of a refrigerant temperature detected by the first temperature detection device, and a saturated liquid enthalpy and a saturated gas enthalpy are calculated on a basis of the refrigerant temperature detected by the second temperature detection device.