SAE J3126_202504

This SAE Recommended Practice is intended to provide technicians with safe and efficient techniques and general equipment recommendations for servicing mobile air conditioning systems in off-road, self-propelled work machines as defined in SAE J1116 and tractors and machinery for agriculture and forestry as defined in ASABE standard ANSI/ASAE S390. Both refrigerants HFC-134a (R-134a) and HFO-1234yf (R-1234yf) are covered. Many service procedures are similar for both refrigerants, but recovery, recycling, charging, and electronic leak detection tools can be unique to each refrigerant. This SAE Recommended Practice provides the air conditioning (A/C) technician with industry-approved best practices to service and maintain mobile A/C systems that use R-134a or R-1234yf refrigerants. Tools and procedures for servicing the refrigerant portion of A/C systems in off-road work machines and agricultural tractors are similar to those used with other mobile A/C systems, with several differences addressed in this SAE Recommended Practice. The adoption of refrigerant R-1234yf, a low GWP alternative with an A2L classification indicating the refrigerant has a low toxicity but is mildly flammable, requires certain tools and precautions for proper service. These guidelines are superseded by detailed procedures, information, and training provided by the OEM specific to the equipment being serviced.