A ventilated conveyor oven is provided. The oven uses a makeup air fan to admit to the plenum extending across the front of the unit and across the top of the unit. Exhaust channels are provided on the sides spaced above and below the conveyor oven entrance and exit and extending across the top to an exhaust fan outlet. The exhaust channels on the top are superimposed over the air makeup plenum. Vertical exhaust plenums are provided at each of three corners, with the fourth corner mounting a control panel and an air makeup external channel thereover.