Huawei’s indirect evaporative cooling system is designed to use theoutdoor air as a “free” cold sourcewhile keeping the data hall supply air isolated from outdoor contaminants and moisture. Its core is theheat exchanger, where heat from the indoor (return) air side is transferred to the outdoor working air side without mixing the two air streams. To enhance heat removal on the outdoor side, aspray systemwets the evaporation media or spray section, and awater pumpcirculates water to maintain uniform wetting and stable evaporation performance.Fansdrive airflow through the indoor and outdoor paths to ensure sufficient heat transfer and maintain the required air volume and pressure. Because outdoor air is involved on the working-air side,air filtersare required to reduce dust and protect the heat exchanger and internal airflow channels, improving reliability and reducing maintenance. Acompressoris not a main component of indirect evaporative cooling because the system primarily relies on evaporation and heat exchange rather than mechanical refrigeration.