Refrigerant: Description and Operation

CAUTION: Avoid breathing A/C Refrigerant-134a and lubricant vapor or mist. Exposure may irritate eyes, nose, and throat. To remove R-134a from the A/C system, use service equipment certified to meet the requirements of SAE J2210 (R-134a recycling equipment). If accidental system discharge occurs, ventilate work area before resuming service. Additional health and safety information may be obtained from refrigerant and lubricant manufacturers.

Refrigerant-134a, like the coolant in the engine cooling system, is the substance in the air conditioning system that absorbs, carries, and then releases heat. Although various substances are used as refrigerants in other types of refrigeration systems, past automotive air conditioning systems used a type called Refrigerant-12 (R-12). This vehicle uses a new type of refrigerant called Refrigerant-134a (R-134a). it is a non-toxic, non-flammable, clear, colorless, liquefied gas. While the R-134a A/C system is very similar to an R-12 A/C system, the differences in the refrigerant, lubricants, and service equipment are important.

NOTICE: R-134a refrigerant is not compatible with R-12 refrigerant in an air conditioning system. R-12 in an R-134a system will cause compressor failure, refrigerant oil sludge, or poor air conditioning system performance. Refrigerant-134a carries a charge of special lubricating oil, polyalkylene glycol (PAG) synthetic refrigerant oil. GM PAG refrigerant oil will have a slight blue tint. The oil is hydroscopic (absorbs water from the atmosphere) and should be stored in closed containers. Use only polyalkylene glycol (PAG) synthetic refrigerant oil for internal circulation through the R-134a A/C system and only mineral base 525 viscosity refrigerant oil on fittings threads and O-rings. If lubricants other than those specified are used, compressor failure and/or fitting seizure is likely to occur.