Abstract: Through comparative experimental research on the performance of three flow path schemes of 5 mm copper tube double-row condensers, namely five-in-five-out, six-in-six-out, and eight-in-eight-out, in the air conditioner as a whole, the results show that the six-in-six-out flow path scheme of the 5 mm copper tube double-row condenser has the best performance in terms of capacity and energy efficiency when operating in a wide temperature range of outdoor ambient temperature from 35 ℃ to 60 ℃. The high pressure of the entire system is the lowest, the difference between high and low pressure is the smallest, and the operation reliability of the entire system is the best. The variance of the outlet temperature of each flow path of the condenser under different working conditions is the smallest, and the flow is the most uniform. Therefore, this scheme is the best flow path among the three flow path schemes. Through comparative experiments and tests with the prototype solution, it was found that the 5 mm copper tube double-row condenser solution can completely replace the 7 mm copper tube double-row condenser solution of the prototype. At the same time, this solution can be extended to multiple models for product development and use, which can reduce the overall machine cost by about 6% and decrease the refrigerant usage of the entire machine by up to 26%. While ensuring product quality, It can also achieve cost reduction and carbon emission reduction, contributing to the country’s dual carbon strategic goals.

Key words: 5 mm copper tube, Air conditioner, Heat exchanger, Condenser diversion, Flow path optimization