In Fig. 4 shows the experimental set up, the tested heat pipe was monitored and recorded by a thermocouple type-K T1-T3 evaporator sections T4-T6 adiabatic sections T7-T9 condenser sections T10 cold water inlet,(oC) T11 cold water outlet, (oC) T12 hot water inlet,(oC) T13 hot water outlet, (oC) a Yogokawa MV1000 data acquisition with ±0.7oC accuracy, it used with type-K thermocouple ±0.5oC accuracy (22 points attached). as shown Fig 4.