Abstract <p>An approach is used in this paper that allows for describing boundary conditions of the third kind under the influence of a heat source on the human body from the standpoint of asymptotic perturbation theory. A woven electric heater with the heat-generating elements made of carbon threads served as a source of perturbations. The obtained results made it possible to find a more accurate mathematical description of the physical processes that occur on the surface of a woven electric heater located directly on the human body. The theoretical justification of the proceeding thermal process confirms the possibility of simultaneous implementation both of thermal action using a woven electric heater and of tracking temperature changes on the surface of a woven electric heater taking into account the response to the impact from a person, which is a novelty. Based on this approach, a program that can be used to simulate thermal processes on the surface of woven electric heaters located on the human body was written. This paper is of interest to specialists involved in modeling processes that occur under the influence of heat sources on the surface of a human body as well as to developers of heating devices based on electrical heating fabric, physiologists, etc.</p>