A non-atmospheric pressure vapor oven system that utilizes a controllable
pressure zone to facilitate fast phase change heat transfer at any
desired temperature to heat or cool flat substrates, and to level
temperatures across different locations of the substrates. The system
enables the use of a heat transfer fluid, such as water, without being
limited to a particular temperature, such as the fluid's natural boiling
point at atmospheric pressure. The system includes a vapor oven (hermetic
enclosure) defining a pressure chamber having sealed entry and exit ports
for transferring an object (e.g., a sheet of paper) with added material
(e.g., toner) through the pressure chamber, and a pressure regulation
apparatus for setting the saturation temperature (boiling point) of heat
transfer fluid inside the vapor oven to an optimal heating/cooling
temperature by selectively controlling the pressure inside the hermetic
enclosure.