What is the main refrigerant used in automotive air conditioning systems nowadays?
3 Answers
Automotive air conditioning refrigerants (commonly known as Freon or refrigerant) currently consist of two main types: non-environmentally friendly R12 and R134a (HFC-134a). Below are the selection criteria for refrigerants: 1. Consider the type of compressor. Different refrigeration compressors operate on different principles. Positive displacement compressors increase pressure by reducing the volume of refrigerant vapor, generally requiring refrigerants with high volumetric cooling capacity. 2. Consider the required cooling temperature. Depending on refrigerant temperature and cooling conditions, choose high-temperature (low-pressure), medium-temperature (medium-pressure), or low-temperature (high-pressure) refrigerants. Typically, the standard evaporation temperature of the selected refrigerant should be at least 10°C lower than the cooling temperature. Selection should also account for the cooling conditions and operating environment of the refrigeration system. Operating condensation pressure must not exceed the compressor's safety limits. Since automotive air conditioning systems can only use outside air as the cooling medium, they are subject to frequent changes in ambient temperature, wind speed, solar radiation, and heat radiation. These operating conditions dictate the use of high-temperature (low-pressure) refrigerants. While R12 was used in the past, R134a is now predominantly selected. 3. Consider the refrigerant's properties. Based on thermodynamic, physical, and chemical properties, choose refrigerants that are non-toxic, non-explosive, and non-flammable. Ideal refrigerants should have good heat transfer characteristics, low flow resistance, and compatibility with materials used in the refrigeration system.
Having driven for over a decade, I've witnessed firsthand the evolution of automotive air conditioning refrigerants. Older vehicles used R12 refrigerant, which provided strong cooling performance but damaged the ozone layer. Later, R134a became the mainstream replacement—much more environmentally friendly, and still used by most cars today. In recent years, R1234yf has gained popularity due to stricter EU regulations requiring greener refrigerants. During my last dealership service, the technician mentioned that nearly all new cars now use R1234yf. While its cooling efficiency is comparable, this refrigerant is significantly more expensive, driving up maintenance costs. As a car owner, I believe R134a remains perfectly adequate—as long as there are no leaks, it keeps the cabin comfortably cool in summer. The key is regular AC system inspections to prevent refrigerant leakage from compromising performance.
Over the years working in auto repair shops, I've handled countless car air conditioning systems. Currently, there are mainly two types of refrigerants on the market: R134a used in most vehicles after 2010, and the newer R1234yf for recent models. The cooling performance between the two is actually quite similar, with the biggest difference being environmental friendliness. R1234yf has a lower global warming potential, complying with the latest European standards. During maintenance, we pay special attention to system labels because mixing refrigerants can damage the compressor. Professional vacuum equipment is required for charging - never attempt to top it up yourself. Nowadays, many car owners discover their new vehicles use R1234yf when changing cars. Although the price per bottle is twice as expensive, the reduced quantity needed makes the overall cost acceptable.
