Abstract: The reliability of electric heating was studied in accordance with the requirements of the UL 60335-2-40-2022 “Safety of Household and Similar Appliances Special Requirements for Heat Pumps, Air Conditioners and Dehumidifiers” standard for rooftop electromechanical heating exported to North America. Based on the characteristics of the roof electromechanical heating structure, the theoretical analysis model of electric heating heat transfer is established, the coupling relationship between the surface temperature and wind speed of the electric heating wire is obtained, and the wind field distribution is determined by simulation, and the test results verify the reliability of the theoretical model and simulation, which provides theoretical basis and engineering guidance for the installation design of roof electromechanical heating.

Key words: Roof unit, Electric heating, Temperature rise, Wind speed