《蒙特利尔议定书》对发展中国家和发达国家逐步淘汰包括R-22在内的氟氯烃制冷剂有严格的时间表。然而，在大多数发展中国家，由于性能和安全问题，高环境温度限制了替代制冷剂的使用。此外，发达国家通过更高的全球变暖潜能（GWP）制冷剂（如HFC和HFC混合物）的过渡导致了大量直接二氧化碳当量排放。必须为发展中国家建立一座桥梁，避免从氟氯烃向氢氟碳化合物过渡，然后再从氢氟碳化合物向低GWP替代制冷剂过渡。 在本文中，我们总结了R-22小型分体式系统替代制冷剂评估的实验活动。根据ANSI/ASHRAE标准37进行实验评估，并根据ANSI/AHRI 210-240标准对性能进行评级。此外，在46℃、52℃和55℃的室外环境温度下对延长试验条件进行了评估。R-22替代制冷剂包括适当的制冷剂混合物（ARM-20b、DR-3和N-20b）。首先使用基准制冷剂对装置性能进行验证，然后将其降下- 随后进行制冷剂评估，包括软优化，以确保制冷剂性能得到充分体现。软优化包括:1）充电优化、2）润滑油和3）流量控制。本文介绍了在不同操作条件下，替代制冷剂与基准制冷剂的相对性能（效率和容量）。最后，我们对R-22在高温地区的替代制冷剂进行了评述。 引用:2016年冬季会议，佛罗里达州奥兰多，会议论文

The Montreal Protocol has a stringent timeline for the phase-out of HCFC refrigerants, including R-22, in both developing and developed nations. However, in most developing nations, high ambient temperatures limit the use of alternative refrigerants due to performance and safety concerns. Furthermore, the developed world’s transition through higher global warming potential (GWP) refrigerants like HFC and HFC blends resulted in significant direct CO2 equivalent emissions. It is imperative to develop a bridge for developing nations to avoid the transition from HCFC to HFC and then from HFC to alternative lower GWP refrigerants. In this paper, we summarize an experimental campaign on alternative refrigerant evaluation for an R-22 mini-split system. The experimental evaluation was performed according to ANSI/ASHRAE Standard 37 and the performance was rated according to ANSI/AHRI 210-240 standard. Furthermore, extended test conditions were evaluated at outdoor ambient temperatures of 46°C, 52°C, and 55°C. R-22 alternative refrigerants included propriety refrigerant blends (ARM-20b, DR-3, and N-20b). The unit performance was first verified using the baseline refrigerant and then drop-in refrigerant evaluation followed including soft optimization to ensure refrigerant performance is adequately represented. The soft optimization included: 1) charge optimization, 2) lubricant, and 3) flow control. The paper presents the relative performance (efficiency and capacity) of the alternative refrigerants compared to the baseline refrigerant at the different operating conditions. We conclude with remarks about the alternative refrigerants for R-22 applications in high ambient temperature regions.