Abstract: A rethermalization oven for heating food is disclosed, characterized by uniform distribution of heat and air through a heating chamber. The oven includes a housing and partitions for defining an outer U-shaped air plenum, a rectangular heating chamber, and a burner chamber. The side panels of the partition contain a plurality of spaced horizontal slots and the rear panel of the partition contains a plurality of spaced openings and horizontal slots of progressively increasing thickness in the directions toward the top and bottom of the housing. A heating element is arranged in the burner chamber for heating the air arranged therein.

Abstract: A conveyor is driven in a helical endless fashion within a horizontally annular baking chamber while carrying products to be baked. The air within the chamber is heated by means of burners disposed beneath the conveyor and in non-parallel relationship thereto. Heated air is drawn through an air permeable cover across the top of the chamber and into an upper air space thereabove. The air is circulated from that upper air space to a lower air space located beneath the chamber. The air is then circulated into the chamber through an air permeable floor disposed across the bottom of the chamber. The permeability of the cover and floor varies in order to assure a uniform passage of heated air therethrough.