ShareHFC134a/HFO1234yf mixture: lower GWP without flammability
A recent study* published in the International Journal of Refrigeration (IJR) by Inha University, South Korea, compared the performance of HFC134a, HFO1234yf and HFO1234yf/HFC134a mixtures at three compositions of 5%, 10% and 15% HFC134a
A recent study* published in the International Journal of Refrigeration (IJR) by Inha University, South Korea, compared the performance of HCF134a, HFO1234yf and HFO1234yf/HFC134a mixtures at three compositions of 5%, 10% and 15% HFC134a with a heat pump bench tester.
HFC134a has a GWP of 1430, which is much higher that the EU MAC Directive’s maximum threshold of 150 for new types of vehicles. Recently, HFO1234yf has been suggested as a possible alternative refrigerant for HFC134a in mobile air-conditioners (MACs) as its COP, capacity and discharge temperature are similar. However, its use raises flammability issues.
In case of HFO1234yf/HFC134a mixtures, flammability decreases as more HFC134a is added and at compositions of over 10% HFC134a, the mixture becomes non-flammable. The amount of charge required for an HFO1234yf/HFC13 mixture is up to 11% lower than that of HFC134a, due to a decrease in density with HFO1234yf.
When the mixture contains 10-11% HFC134a, it is both virtually non-flammable and azeotropic and has no ODP and a GWP below 150, making it an environmentally friendlier and regulatory compliant solution for various HFC134a applications with minor modifications.
* Y. Lee et al, Performance of virtually non-flammable azeotropic HFO1234yf/HFC134a mixture for HFC134a applications, IJR, vol. 36-3, May 2013
This article from the IJR can be downloaded via the IIR’s Fridoc database (free for IIR members within the framework of their quota of free downloads): www.iifiir.org or info@iifiir.org
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HFC134a has a GWP of 1430, which is much higher that the EU MAC Directive’s maximum threshold of 150 for new types of vehicles. Recently, HFO1234yf has been suggested as a possible alternative refrigerant for HFC134a in mobile air-conditioners (MACs) as its COP, capacity and discharge temperature are similar. However, its use raises flammability issues.
In case of HFO1234yf/HFC134a mixtures, flammability decreases as more HFC134a is added and at compositions of over 10% HFC134a, the mixture becomes non-flammable. The amount of charge required for an HFO1234yf/HFC13 mixture is up to 11% lower than that of HFC134a, due to a decrease in density with HFO1234yf.
When the mixture contains 10-11% HFC134a, it is both virtually non-flammable and azeotropic and has no ODP and a GWP below 150, making it an environmentally friendlier and regulatory compliant solution for various HFC134a applications with minor modifications.
* Y. Lee et al, Performance of virtually non-flammable azeotropic HFO1234yf/HFC134a mixture for HFC134a applications, IJR, vol. 36-3, May 2013
This article from the IJR can be downloaded via the IIR’s Fridoc database (free for IIR members within the framework of their quota of free downloads): www.iifiir.org or info@iifiir.org
Remember to log in or register first!