Drinking water distribution networks distribute a water-air mixture through the pipes given the inherent conditions of fluid conduction. These air bubbles are measured by the volumetric meters that are used to bill water consumption. Inaccurate measurements are detrimental for both the client and the supplier. However, there are non-return valves that have the ability to reduce the size of air bubbles traveling through the water lines to improve the accuracy of these meter readings. In this investigation, a CFD simulation of the behavior of the pressure and the volumetric fraction of the biphasic water-air flow was performed to estimate the performance of these devices based on the monitoring of these two variables. It was observed that the non-return valve operating with a water-air ratio of 90/10 respectively and at an average flow rate of 1.35 m/s in the pipeline, the size of the air bubbles and their volumetric fraction is reduced from concentrations from 80% to 45%. The results of the pressure drop of the non-return valve suggest that for the stem equilibrium position it produces a pressure drop of 9 PSI in the two-phase water-air flow stream