• Subscribe
  • In Print
    1. In the Bay
    2. Shop Equipment

    How is the refrigerant HFO-1234yf different from R-134a?

    Aug. 13, 2014

    Refrigerant R-134a, also known HFC-134a, is a hydrofluorocarbon (HFC) refrigerant. HFO-1234yf is a hydrofluoro-olefin (HFO) refrigerant.

    Both types of refrigerants are composed of hydrogen, fluorine and carbon atoms. However, with HFC refrigerants, the atoms are connected by single bonds between the atoms, whereas the atoms in HFO refrigerants at least one double bond between the carbon atoms.

    While HFC-134a has been one of the global standard automotive air conditioning refrigerants, it will not meet the European Union’s Mobile Air Conditioning (MAC) Directive that reduces the climate impact of air conditioning in cars sold in the EU.

    HFO-1234yf, which has physical properties similar to R-134a, complies with the directive because of its low Global Warming Potential (GWP) and has the potential for direct substitution of into existing R0134a automotive air conditioning systems with minimal modification.

    About the Author

    David A. Kolman | Contributor - Fleet Maintenance

    There are differences when servicing HFO-1234yf motor vehicle air conditioning systems due to the mild flammability of HFO-1234yf and other product differences from R-134a.
    Refrigerant emissions from mobile air conditioning systems have been a dominating source of greenhouse gases to the atmosphere and trucking industry experts expect that air conditioning systems for heavy trucks will be changed to refrigerants that have a lower GWP than the current R-134a.
    While cabin air filters should be replaced according to the guidelines in the owner’s manual, it is advisable to change the filters on a seasonal basis because of the pollutants that are prevalent in different seasons.