In this study. a newly developed test set-up installed in a thermal vacuum chamber and the thermal performance test performed with this set-up is described. Evaporator is simulated by using mounted resistive heaters on it whereas two black painted aluminum plates in contact with the condenser are used to remove heat from heat pipe. Thanks to the vacuum level obtained in the chamber. https://fitnessgravesyardes.shop/product-category/upper-led-display-board/