An experimental study is conducted on the internal cooling-heating crank thermosyphon oriented with respect to horizontal. Bent geometry of the thermosyphon is sometimes needed to use because of the limited space for the straight thermosyphon to be installed. Therefore, in the present study, the crank-shape thermosyphon is investigated on the heat transfer coefficients and the critical heat fluxes.  Experiments on water filled tubes are conducted to investigate the internal cooling –heating offset thermosyphon. Heat transfer in tilted annular two phase closed thermosyphon has been studied experimentally. The effect of heat flux, inclination angle and the evaporator to condenser length ratio on the heat transfer coefficient has been investigated in details. The evaporator to condenser ratio was varied from 0.25 to 1.6. The inclination angle was changed to be 15°, 30°, 45°, 60° and 90°. The heat flux was taken as: 1.33, 2.66, 3.99, 5.32 and 6.65 kW/m². The results indicated that, the maximum overall heat transfer coefficient occurs at evaporator length to condenser length ratio 0.5 with an inclination angle of 60°. At evaporator to condenser length ratio of unity, the maximum overall heat transfer coefficient occurs at L_e=L_c = 20 cm. The thermal performance increases when the heat transfer rate was increased.