The “air flow deviator”, is an air barrier module used on built in and free standing ovens that uses the existing cooling air flow, at normal speed or at a higher speed, to create a hot air barrier between the oven cavity (hot) and the surroundings (room temperature). Installation of this device allows to overcome a number of inconveniences such as the hot air blasts, the heat dispersion with consequent lengthening of cooking time, the increase in consumption of electricity / energy and superficial cooking and glazing non homogenous.