In this work, problems related to the corrosion and sedimentation in cooling tower and the decrease in the amount of evaporation rate are investigated experimentally, using loop test which is similar to the cooling tower system. The input and output water stream in the loop test are analyzed in different time intervals, different amount of evaporation, different amount of the outlet water and make up water stream. The first analyzes indicate on the increase in the amount of dissolved material, concentration cycle and also the increase in the amount of evaporation rate and consequent corrosion problems and sedimentation. However, adjusting the amount of makeup water and the water outlet provides the acceptable results. Changes in conditions due to each analyze are illustrated in curves.