substantially unrestricted air flow through the heater 122 the housing 116 defines a second passage 152 around the heater 122 between the proximal end 116p and the distal end 116d of the housing 116 with a second small aperture 124b defining a portion of the second passage 152 the second passage 152 includes a divider plate 154 coupled to the inlet opening 126a of the nozzle 126 for continuously passing air from the second passage 152 to the nozzle 126 with a valve controlling the volume of air passing from the proximal end 116a through the heater 122 to the nozzle 126 for the second embodiment of fig4 the valve comprises a thermostatic metal panel 156 which is secured within the housing 116 for movement on a first side of the divider plate 154 the top side in the illustrated embodiment within the second passage 152 also see fig5 8 a valve panel 158 is secured within the housing 116 for movement on a second side of the divider plate 154 the bottom side in the illustrated embodiment between a first position wherein the inlet opening 126a of the discharge nozzle 126 is substantially open illustrated in solid line drawing in fig4 and a second position wherein the inlet opening 126a of the discharge nozzle 126 is substantially closed illustrated in dotted line drawing in fig4 at least one link element 160 is connected between the thermostatic.