Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Thermodynamic Properties of R-227ea, R-365mfc, R-115, and R-13I1



Eric W. Lemmon, Roland Span


Equations of state are presented for the refrigerants 1,1,1,2,3,3,3-heptafluoropropane (R-227ea) and 1,1,1,3,3-pentafluorobutane (R-365mfc). Typical uncertainties of properties calculated with the new equations are 0.2 % in density, 1 % to 2 % in heat capacities and liquid-phase sound speeds, and 0.2 % in vapor pressure. Where data are available, uncertainties in vapor-phase sound speeds are generally less than 0.1 %. Equations of state for trifluoroiodomethane (R-13I1) and chloropentafluoroethane (R-115) are also given in an appendix for applications where systems using these banned substances are being upgraded or replaced with modern refrigerants, and properties of the old working fluids are needed in the design of the new system.
Journal of Chemical and Engineering Data


Lemmon, E. and Span, R. (2015), Thermodynamic Properties of R-227ea, R-365mfc, R-115, and R-13I1, Journal of Chemical and Engineering Data, [online], (Accessed February 25, 2024)
Created November 13, 2015, Updated June 2, 2021