In Fig. 4 shows the experimental set up, the tested heat pipe was monitored and recorded by a thermocouple type the evaporator, adiabatic and condenserof thermosyphon equal tree section. Ten thermocouples were installed to data Yogokawa MV1000 data acquisition with ±0.7oC accuracy, it used with type-K thermocouple ±0.5oC accuracy (22 points attached). was used with type K thermocouples to the inlet and outlet of the heating jacket and cooling jacket,thermocouple were attached to the Thermosyphon a case modifying the inclination angle of evaporator and condenser sections 0 60 90o and data logger were recorded. These were three points on the condenser, three points on the evaporator and three points on theadiabatic section.