Q. How do vacuum ovens generate heat?

Answer

Because there is no way for heat to move around inside of a vacuum the load inside of the chamber must make direct contact with a hot surface in order to be heated or dried. The heat may be transferred from the side walls to the sliding shelves here or the carrier plates and shelves can be heated directly. A consistent temperature may be maintained throughout the space using air jackets because the heat generated by an air chamber that surrounds the interior helps maintain the temperature. Having said that this process is rather time-consuming.