Advantages and Disadvantages
ADVANTAGESCost - R-134a is generally much cheaper than R-12 or any of the other alternative refrigerants currently available.
Environmentally Friendly - R-134a has been scientifically tested to be safe for the ozone.
Industry Wide Support and Service - Recycling and service equipment are widely available for R-134a systems.
Recyclable on Site - R-134a can be recycled on site using designated recycling equipment. If a refrigerant has been contaminated with an unknown blended alternative, the refrigerant can not be recycled on site.
Stable Mixture - R-134a is the only approved alternative which is not a blend of other refrigerants. R-134a does not separate or settle out providing for consistent operating characteristics.
Detectable - R-134a is detectable using current leak detection methods designed for R-12.
DISADVANTAGES
Less Efficient than CFC-12 - In systems originally designed for R-12, retrofitting with R-134a may produce less than satisfactory results. Using R-134a results in higher head pressures and higher compressor outlet temperatures. To provide satisfactory cooling performance a larger condenser or an additional cooling fan may be needed to remove the excess heat.
NOTE: In newer vehicles designed to use R-134a, cooling performance is similar to older R-12 equipped vehicles.
Higher Pressures - Higher head pressures may hasten the failure of an A/C compressor which is already severely worn.
Leakage - R-134a is made of molecules which are smaller than that of R-12. After retrofitting a R-12 system with R-134a, the smaller molecules combined with the higher operating pressure may result in leaks which were previously undetectable.
Retrofitting Cost - If retrofitting requires replacement of the condenser or compresssor, the total cost of the job may greatly exceed the cost of continued service with R-12.