Abstract: An experimental study was conducted to investigate the reasons for the fluctuation in the cooling capacity of a certain 36000 Btu/h capacity home air conditioner, which was determined to be non-compliant based on the inspection results during the mass production quality control. Six optimization schemes were proposed and experimentally studied from the perspectives of the evaporator, condenser, and compressor to address the reasons for the fluctuation in the cooling capacity of the air conditioner. The results show that the overheating situation of the prototype evaporator flow path is consistent with the wind speed distribution on the evaporator surface. Optimizing the evaporator flow path from 9 inlets and 9 outlets to 10 inlets and 10 outlets has a good effect on the fluctuation of the whole machine performance. At the same time, replacing a certain brand's 26.5-liter compressor based on this scheme can significantly improve the fluctuation of the whole machine's performance, with an increase in capacity of up to 4.7% and an increase in energy efficiency of up to 7.1%. This study provides an effective solution for the capacity fluctuation of the whole machine, and provides relevant guidance for the peers to encounter similar problems in the future.

Key words: Air conditioner, Capacity fluctuation, Evaporator diversion, Flow path optimization