The presented doctoral dissertation entitled "Research of the possibility of enlarging the dimensions of the thermal node of the single crystal growth device by the horizontal crystallization method" is focused on the design and its implementation in order to increase its lifetime. In my work I partially focused on the importance of single crystals’ practical application and the current state of industrially used production methods. Based on the acquired knowledge and all the advantages of the method of Horizontally Guided Crystallization and based on the Study of Physico-Chemical Effects, modern construction materials and principles were selected. Subsequently, a design of a modernized thermal node with combined insulation was created and its temperature fields were monitored by means of simulations. The results obtained contributed to the confirmation of the assumptions about the thermal load and allowed for proper function of the vacuum chamber cooling. After all necessary adjustments to the vacuum chamber and its subsystems, a thermal node was produced and mounted. Its correct functionality was experimentally verified directly in the crystal production process and the results from the simulations were verified. After a series of crystallization processes, a wear analysis was performed, with the result that the lifetime of the proposed thermal node structure was several times higher than that of the conventional design.