How is condensation controlled in high humidity environments?
Outdoor air is pre-conditioned and dehumidified in the primary air AHU, along with any return air needed to make up the primary air total. The building is maintained at a slight positive pressure with respect to the outside to control infiltration of humid air. Once the dehumidified air is supplied to the space, the air dew point is monitored as well as the secondary water temperature, the control system using this data in the control strategy to provide conditions where condensation will occur. There are a range of strategies that can be employed to suit any particular project. These include re-setting the SCHW water temperature up; switching the SCHW pump off for a period; overriding the primary air temperature control to increase the rate of dehumidification at the primary air cooling coil; at start-up after a weekend, operation with primary air only until the space humidity is reduced to unacceptable level, and more. Refer to the Controls section of the Dadanco System handbook.
