Liquid-liquid equilibrium (LLE) for the system water+acetic acid+1-heptanol have been studied at atmospheric pressure in the temperature range of 278.1-313.1 K. The raw experimental data of this work, together with the available experimental data in the literature on the same ternary system, are analyzed and compared. The analysis is achieved by using three versions of the well-known UNIFAC model. The comparison is made in terms of root-mean-square (RMS) in temperature and composition, maximum deviation (MAXDEV) in temperature, and the average-absolute deviations (AAD) in compositions. In all of these models, the interaction parameters employed are those provided by Aspen Plus library. All models predict much lower deviations and RMS values for the data of this study than those for the data of the literature.