This paper demonstrates the influence of low Rayleigh vibration on thermodiffusion measurement in microgravity environment. The goal is to show how the variation of certain parameters such as frequency and amplitude of translational vibrations would impact the results obtained from the ISS experiment. Precisely, impact of change in low Rayleigh vibration on the separation of a component is studied for each experimental run. ISS experimental data are obtained based on optical digital interferometry in a reduced gravity environment. The experiment is done in a cubic cell containing an aqueous solution exposed to a lateral temperature gradient. A mixture of water and isopropanol of different initial concentrations with positive and negative Soret coefficient is chosen as the test fluid. Collected data are analysed by image processing. Results show maximum separation of components for the case without any forced vibration. Moreover, an increase in Rayleigh number corresponds to decrease in the separation of components.