Freon 134a is an HFC, a zero ozone depletion potential refrigerant with properties very similar to Freon12. It’s used as a pure refrigerant in traditional Freon 12 applications, including appliances (air conditioners, refrigerators), automotive air conditioning, construction, food processing and storage, industrial refrigeration), and supermarkets. It’s also used as a component in refrigerant blends targeted for Freon 502 and Freon 22 applications. In addition, Freon 134a is being used in the retrofi t of many existing Freon12 and 502 installations, including centrifugal chillers, semihermetic, reciprocating, and screw refrigeration applications, industrial refrigeration plants, and some hermetic compressor applications. Many types of equipment have successfully made the transition from Freon12 to Freon134a. You’ll fi nd new standard equipment for applications such as automotive air conditioning, specialized air conditioning or climate control applications, positive-pressure centrifugal chillers, medium temperature commercial refrigeration, refrigeration appliances, industrial refrigeration plants, and transport refrigeration. Generally, new equipment will be shipped by the manufacturer with a compatible lubricant already charged. Of course, you should always follow the manufacturer’s recommendations. But here are some things to consider:
Miscibility between refrigerant and oil is critical for most equipment designs to ensure oil return to the compressor. Freon 134a is not miscible with mineral oils. Various equipment manufacturers recommend polyolester (POE) and polyalkylene glycol (PAG – only for automotive air conditioning) as lubricants for Freon134a systems. POE and PAG absorb moisture quickly. Handle them carefully and avoid prolonged exposure to air. Manufacturers have engineered new equipment using Freon134a to have the equivalent energy effi ciency of Freon12 systems. However, there are some points to keep in mind: At evaporator temperatures below 5°F (-15°C), the pressure ratio of Freon134a rises in relation to Freon12 and capacity may drop off . Always check with the equipment manufacturer for specifi c recommendations on low-temperature applications. Equipment manufacturers are using innovations like liquid subcooling to enable Freon134a systems to equal the performance of Freon12 systems.