Air handling units analysis

Case Study: Simultaneous cooling and humidification

In this case study, we have been dealing with simultaneous cooling and humidification. Cooling increases relative humidity, therefore it is not desirable to humidify during the cooling regime. Humidifying shall be used mainly during the heating regime because heating decreases the relative humidity. The problem occurred in July. The AHU was humidifying due to unreasonably high minimal required indoor relative humidity. Moreover, there was no condition that can prevent simultaneous cooling and humidification in the control system. Thanks to Mervis Analytics, this problem was discovered. The first quick fix was a manual switch-off of the humidifiers during summer. Complex improvement of AHU control logic is in preparation. However, even a simple manual switch-off of humidifiers saved more than ten thousand USD per year. The first picture captures a faulty state, while the second picture captures fault-free operation after the manual switch-off of the humidifiers.