Air handling units analysis

Case Study: Simultaneous heating and cooling

In this case study, we have been dealing with simultaneous heating and cooling. More specifically, a heating valve and a cooling valve were both opened at the same time. It caused a problem during spring and autumn when both boiler and chillers were on. This is an example of a fault that can remain hidden for a long time because it does not result in comfort violation nor alarm in BMS. It also cannot be easily observed during AHU inspection. But it can have a severe impact on energy consumption. In this particular case, the cause of the problem was an error in the AHU control logic. After detecting this fault by Mervis Analytics, changes in the control logic were made, and the problem was solved, as can be seen in the pictures. The first one captures a faulty state, while the second one captures fault-free operation after control logic change.