122 the magnetrons 260 will be energized and emit microwave energy into the wave guides 272 which will conduct the energy into the rotating chamber 236 in addition the control signal to triac 158 will energize the augmentation heater 142 and heat the air that moves past it the recirculation damper solenoid 268 is activated by the controller 100 thereby opening the recirculation baffle permitting the exhaust air to be recirculated into the upper plenum 274 where it is mixed with the intake air and recirculated through the rotating chamber 236 in addition the controller activates the exhaust damper solenoid 150 thereby closing the main exhaust damper 242 to prevent venting the exhaust air to the outside atmosphere and causing all exhaust air to be recirculated further accelerating the temperature increase of the air the intake air will obtain heat energy from 1 the heat exchanger 323 2 convection due to the warm components in the lower plenum 234 3 the recirculated exhaust air and 4 the augmentation heater 278 before entering the chamber the fabric drying system is now operating within the parameters of the initial stage of the drying cycle during this stage the magnetrons 260 are energized the augmentation heater 278 is energized the recirculation baffle is open and the main exhaust damper 242 is closed this initial stage of the drying cycle serves to quickly bring.