Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
Your Airloop will look: Humidifier => Cooling Coil => Heating Coil => Fan
You will use SetpoinManager:MultiZone:Humidity:Minimum and SetpoinManager:MultiZone:Humidity:Maximum in the nodes after the humidifier and the cooling coil, respectively. To do this, you have to specify the humidity ratio for the spaces. Decide what is your space setpoint and calculate the humidity ratio from there. From your requirements (28C and between 45% RH to 55% RH) the minimum HR would be 0.0106 and the maximum 0.013. When looking at the results, either look at the zone humidity ratio or export both RH and dry bulb temperature.
You will also need to specify the Control Variable for the Controller:Watercoil for your cooling coil to be TemperatureAndHumidityRatio.
You cooling coil can be any type accepted in an airloop, so it does not necessarily need to be Coil:Cooling:WaterToAirHeatPump:EquationFit, it could also be a Coil:Cooling:Water or any other type your system uses.
You said that you do not need heating, but you could need to reheat the air after dehumidification to prevent overcooling (I am not sure if this is allowed by code in a data-center).
You can find an example of this arrangement in
5ZoneWaterCooled_MultizoneMinMaxRHControl of the Energyplus example files.
