AHU Heat Exchanger Performance Tracking During the Building Operational Phase

Building operation accounts for roughly 30% of the world's energy use, with space heating, space cooling, and ventilation accounting for 43%. Given this significant impact, ensuring these systems operate efficiently is crucial. There is a lack of Key Performance Indicators (KPIs) that focus on ensuring that the heat exchanger in Air Handling Units (AHUs) performs efficiently. Therefore, four contextual KPIs have been proposed and evaluated on two datasets from operational AHUs that supply an educational building in Denmark. To allow the proposed KPIs to be used for different heat exchangers, virtual sensors were developed to monitor the air temperature between the heat exchanger and the heating/cooling coils on the supply side, as this sensor tends to be missing in AHUs. The proposed KPIs, in combination with the traditional heat recovery efficiency KPI, offer a more comprehensive understanding of the heat exchanger's performance than the heat recovery efficiency alone.