The article presents the study of heat generation in the heating element, revealed the working temperature and the nature of the distribution of the temperature field. A method of experimental research has been developed that allows one to determine the thermophysical parameters and the distribution of the temperature field on the surface of the materials under study. It is established that the phase transition temperature is shifted by 2 ° C, and the measured thermal conductivity increased for modified heptadecane to a value of 0.3 W / m ° C. It was revealed that the use of a material with a phase transition provides the effect of a self-adjusting thermal contact. Improvement of thermal contact occurs within 20 seconds due to a phase transition in nano-modified heptadecane with its volume increasing by 2%. © Published under licence by IOP Publishing Ltd.