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HVAC System - Manual

Refrigerant R-134a



NOTE: R-134a is the only approved refrigerant for use in this vehicle. The use of any other refrigerant may result in poor system performance or component failure.

NOTE: Use only Polyalkylene Glycol Synthetic Refrigerant Oil (PAG) for internal circulation through the R-134a A/C system and only 525 viscosity mineral oil on fitting threads and O-rings. If lubricants other than those specified are used, compressor failure and/or fitting seizure may result.

NOTE: R-12 refrigerant and R-134a refrigerant must never be mixed, even in the smallest of amounts, as they are incompatible with each other. If the refrigerants are mixed, compressor failure is likely to occur. Refer to the manufacturer instructions included with the service equipment before servicing.

Similar in function to the engine coolant, the refrigerant is the medium within the A/C system that absorbs, carries, and releases heat. This vehicle uses Refrigerant-134a (R-134a), a non-toxic, non-flammable, clear, colorless, and liquefied gas.

While the R-134a A/C system is very similar to an R-12 A/C system, the differences in the lubricants and in the service equipment are important. R-134a carries a charge of a special lubricating oil, Poly-Alkylene Glycol (PAG) refrigerant oil. The GM PAG refrigerant oil has a slight blue tint. The oil is hydroscopic (water-absorbing) and required storage in a closed container.