本SAE推荐实践的目的是提供将CFC-12(R-12)系统改装为HFC-134a(R-134a)的维修程序，同时保持空调(A/C)系统的性能和完整性。当结合良好的服务实践和车辆制造商对改装其车型的建议（如果有）时，本程序中概述的步骤是完整的。 应使用单独的CFC-12（R-12）和HFC-134a（R-134a）维修设备，包括制冷剂回收/再循环（R/R）、维修歧管、真空泵和加注设备，以保持制冷剂和移动式空调系统的纯度。这一程序将最大限度地减少制冷剂向大气的释放，并将保持再循环的CFC-12(R-12)和HFC-134a(R-134a)供应品。 本文件适用于用于冷却汽车、轻型卡车和其他具有类似CFC-12（R-12）系统的车辆乘客舱的空调系统。由于近年来的技术进步，建议将该程序用于20世纪80年代中期及以后生产的常见车辆平台。在此时间段之前生产的车辆可能需要额外的改装要求。本文件不包括在具有密封系统的冷藏货物移动车辆上使用的空调系统。 本文件只有与SAE J1657“移动式空调系统中替代CFC-12（R-12）的改造制冷剂的选择标准”的要求相结合时才是完整的。

The purpose of this SAE Recommended Practice is to provide a service procedure for retrofitting a CFC-12 (R-12) system to HFC-134a (R-134a) while preserving performance and integrity of the air-conditioning (A/C) system. The steps outlined in this procedure are complete when combined with good service practices and the vehicle manufacturer's recommendations (if available) for retrofitting their models. Separate service equipment, for CFC-12 (R-12) and HFC-134a (R-134a), including refrigerant recovery/ recycle (R/R), service manifolds, vacuum pumps, and charging equipment shall be used to preserve the purity of the refrigerants and the mobile A/C systems. This procedure will minimize release of refrigerant to the atmosphere, and will preserve the integrity of the recycled CFC-12 (R-12) and HFC-134a (R-134a) supplies. This document applies to A/C systems used to cool the passenger compartment of automobiles, light trucks, and other vehicles with similar CFC-12 (R-12) systems. Due to technical advancements in recent years, this procedure is recommended for common vehicle platforms produced in the mid-1980s and later. Vehicles produced before this time period may require additional retrofit requirements. A/C systems used on mobile vehicles for refrigerated cargo that have hermetically sealed systems are not covered by this document. This document is only complete when combined with the requirements of SAE J1657 "Selection Criteria for Retrofit Refrigerants to Replace CFC-12 (R-12) in Mobile Air-conditioning Systems."