R-407C

{{Short description|Mixture used as a refrigerant}}

File:R407C_container.png

R-407C is a mixture of hydrofluorocarbons used as a refrigerant. It is a zeotropic blend of difluoromethane (R-32), pentafluoroethane (R-125), and 1,1,1,2-tetrafluoroethane (R-134a). Difluoromethane serves to provide the heat capacity, pentafluoroethane decreases flammability, tetrafluoroethane reduces pressure.[http://home2.btconnect.com/grss/Web/R407C.htm A brief history of refrigerant] {{webarchive|url=https://web.archive.org/web/20110718150305/http://home2.btconnect.com/grss/Web/R407C.htm |date=2011-07-18 }} R-407C cylinders are colored burnt orange.

This refrigerant is intended as a replacement for R-22 in existing refrigerators.{{Cite web |title=The Switch Is On For Refrigerants |url=https://cen.acs.org/articles/84/i17/Switch-Refrigerants.html?ref=search_results |access-date=2025-03-09 |website=Chemical & Engineering News |language=en}} R-22 production will be phased out by 2020 as per the Montreal Protocol as the chlorine in R-22 can lead to ozone depletion.{{cite web|title=Unwrapping The Mystery Of R-407C|url=http://www.achrnews.com/articles/114247-unwrapping-the-mystery-of-R-407C|website=www.achrnews.com|accessdate=27 June 2016}} As the components in R-407C lack chlorine it does not contribute significantly to ozone depletion in the stratosphere. Despite improved environmental impact with respect to ozone depletion, R-407C still has a calculated 100-year global warming potential of 1774,{{Cite web |last=US EPA |first=OAR |date=2023-09-25 |title=Technology Transitions GWP Reference Table |url=https://www.epa.gov/climate-hfcs-reduction/technology-transitions-gwp-reference-table |access-date=2025-03-09 |website=www.epa.gov |language=en}} only slightly lower than calculated value of 1960 for the R-22 refrigerant it replaces.{{Citation |title=The Earth’s Energy Budget, Climate Feedbacks and Climate Sensitivity |date=2023 |work=Climate Change 2021 – The Physical Science Basis: Working Group I Contribution to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change |pages=923–1054 |editor-last=Intergovernmental Panel on Climate Change (IPCC) |url=https://www.cambridge.org/core/books/climate-change-2021-the-physical-science-basis/earths-energy-budget-climate-feedbacks-and-climate-sensitivity/AE57C97E588FF3060C7C7E47DD4F3C6E |access-date=2025-03-09 |place=Cambridge |publisher=Cambridge University Press |isbn=978-1-009-15788-9}} The use of R-407C and other high GWP hydrofluorocarbon refrigerants is being phased out worldwide in accordance with the Kigali Amendment to the Montreal Protocol. Its use was barred for many applications in the United States on 1 January 2025 with near-complete phaseout planned by 1 January 2028.{{Cite web |last=US EPA |first=OAR |date=2023-09-19 |title=Technology Transitions HFC Restrictions by Sector |url=https://www.epa.gov/climate-hfcs-reduction/technology-transitions-hfc-restrictions-sector |access-date=2025-03-09 |website=www.epa.gov |language=en}}