Abstract: An adapter manifold to supply untempered outside air to a kitchen or other ventilating hood is in the form of an elongated box structure which has a plurality of serially arranged outlets communicating with the interior of the manifold and extending outwardly therefrom. The adapter manifold is connected to the existing hood by cutting holes in the front wall of the hood so that the manifold tubes can project into the hood and direct streams of outside air against the grease filter. The adapter manifold enables use of outside air to facilitate exhausting of fumes and odors without causing loss of substantial amounts of tempered or conditioned inside air.