The Helios EHR‑K 15÷40÷20 is an enclosed electric duct heater designed for integration into ventilation duct systems alongside duct fans. It features a galvanized steel sheet housing with flanged inlet and outlet connections for straightforward installation. The heater is equipped with low surface temperature elements, ensuring safe operation. A built-in terminal box on the housing allows for the selection of multiple heating stages. To protect against overheating, the unit includes two thermal cut-outs that activate at 90 °C and 130 °C, ensuring reliable and safe performance in continuous operation.