outlets 48 through the chamber 38 and back to inlets 44 the inlets 44 are preferably spaced apart and perpendicular to the horizontally extending trays 45 see fig3 and 4 so that the circulated steam air or warmed air can pass over the top and parallel to each tray 45 and around food products placed thereon a preferred low pressure steam generator has a pan 43 which is further defined by an upwardly projecting ridge 56 see fig3 extending around an upper edge of the pan 43 the ridge 56 has a horizontally extending surface 58 in the form of a flange which extends from the ridge 56 to the side wall 28 and partition 40 and to a location adjacent doors 14 16 a pan cover 42 has a downwardly depending peripheral flange 60 around a top surface 62 see fig2 which rests on surface 58 and completely covers the opened top of pan 43 the pan cover 42 further is provided with a layer of insulation 64 preferably beneath the surface 62 see fig2 and the flange 60 has openings 66 formed on opposite sides thereof to permit steam generated in pan 43 to flow into chamber 38 the pan cover 42 also serves to prevent circulating air from contacting the surface of the water in the pan and evaporating the water or heating the air above a desired setpoint while the above described pan form steam generator is preferred quite obviously any other conventional steam generator in or outside cabinet 12 could be used the doors 14 16 are provided on their interior lower edge portion with a condensation deflection shield 68 see fig4 which extends over the horizontally extending surface 58 to permit any condensation from the inside surface of doors.