The thermosyphon is simple but effective heat transfer devices. It is a vertically oriented wickless heat pipe with liquid pool at the bottom. Working fluid transports a large amount of heat from evaporator to condenser section. Heat enters through the evaporator section, then generated vapor rises and passes through the adiabatic section and reaches to condenser section. In the condenser, vapor condenses and gives up its latent heat. The condensate backs to the evaporator section by natural gravitational force [1]. A schematic of the working principle of the thermosyphon is shown in Fig. 1.