Abstract: A gas cooking appliance, having burner units mounted on an upper cooktop and an oven cavity arranged below the burner units, incorporates a fan for generating a flow of cooling air within the appliance, with the cooling air extending along an at least back and top wall portions of the oven cavity. The cooling air exits the appliance through a frontal gap formed between a door of the oven cavity and an upper frontal portion of the appliance. The burner units have associated combustion air inlets which are isolated from the flow of cooling air by being disposed in a chamber formed by sealing an isolation pan beneath the cooktop. The cooktop is formed with a plurality of openings for permitting a flow of combustion air to be drawn into the chamber for mixing with a regulated flow of combustion gas. With this arrangement, the gas burner units are isolated from the flow of cooling air within the appliance to enhance the operation of the burner units, particularly during low or simmer settings.