A field study of thermal environment and thermal comfort under air carrying energy radiant air-conditioning system (ACERS) and split air conditioner was conducted in south-central China. The results reveals that the ACERS can create a comfortable thermal environment with small vertical temperature gradient. Based on the regression equation of thermal sensation vote and operative temperature, it is found that the neutral temperature in ACERS is about 28 degrees C in summer and 18 degrees C in winter, while in split air conditioner, the temperature is about 26.1 degrees C and 19.3 degrees C. Besides, the comfortable temperature range for 80% acceptability in ACERS is 25.5-30.7 degrees C in summer and 13.8-22.2 degrees C in winter, and the corresponding range of split air conditioner is 23.9-28.3 degrees C and 16.7-21.8 degrees C. The results show that the ACERS has a larger temperature adjustment range compared to the split air conditioner and the thermal comfort stability of ACERS is better. The actual comfortable temperature range is wider than the theoretical value calculated by PMV-PPD equation, and the reason may be that people in their long-term life have been adaptable to the environment. This research is helpful for the design and operation of air-conditioning system in future and provides the theoretical basis for indoor temperature setting in this area. (C) 2018 Elsevier B.V. All rights reserved.