Humidification Made Simple:
What is the difference between a dew point system and an enthalpy control system?
Dew Point Control System Operation
A point near the saturation line and under the target point is first determined in the h-x diagram.
The system must be heated before humidification. The point under the target point is then achieved through maximum humidification. Since the process involves an adiabatic method in which temperature decreases during humidification, the system must again be heated when the target point is reached.
The humidification process in dew point control is employed in areas which show very high levels of relative humidity. However, the higher the relative humidity, the more difficult it is to carry out humidification. In addition, the necessity of heating before and after the humidification process makes two damper registers necessary in the air conditioning system. As a result, a dew point control system proves to be less energy-efficient.
Enthalpy Control System Operation
The more energy-efficient variant of enthalpy control is therefore better suited for this process. In this method, the air is heated to the target air temperature plus the temperature required for the adiabatic humidification process.
The adiabatic humidification causes the target point to be achieved exactly, during which time the air temperature decreases by the value previously included in the calculation. Because the process takes place in a range with high temperature values and low relative humidity values, humidification can be carried out very easily and sensibly from an energy standpoint.