Measurements of the rates of condensation of a steam, methanol and benzene vapor in the presence of air on a short horizontal tube for wide ranges of inlet air concentrations and vapor flow rates were carried out. The observed vapor phase heat and diffusion fluxes were compared with results of the authors’ previous numerical solution to heat and mass transfer on a cylinder with diffusive surface mass suction and injection under laminar forced now conditions. By considering the results of our previous numerical solution and the present experiments, a new method for simulation of condensation of vapors in the presence of noncondensable gas on a short horizontal tube was proposed and compared with the experimental data. The effect of noncondensable gas on the rate of condensation was also discussed.