In this paper, a comparison between a common and a novel prototype of freeze dryer has been considered. A freeze dryer does the action of drying based on freezing the product fluid in low pressure along with a sudden phase change. Using correct assumptions, the freezing heat, freezing time, drying time, and vacuum creating time have been calculated. The freeze dryer was designed in CATIA software based on a new P-T diagram cycle. The novel design is able to work as hot-air dryer and also vacuum dryer, as well as freeze dryer in vacuum. No need to extra refrigerator and the use of separate cycle for drying are two advantages of the novel design. A comparison between the capabilities of the classical and the novel designs suggests that the use of novel design as a domestic device would satisfy the users.