Abstract: A humidity control system and method for controlling the humidity of ambient air is disclosed. The system includes a humidification and dehumidification systems to increase and/or decrease the humidity level of an indoor space and a sensor to sense ambient conditions of the space. The system further includes a controller that receives a humidity setpoint for the indoor space, determines the humidity level associated with the indoor space, compares the determined humidity level to the humidity setpoint, and causes activation of one of a humidification system or a dehumidification system. In response to causing the activation of one of the humidification or dehumidification system, the controller initiates a lockout condition during which the other of the one of the humidification or dehumidification system is prevented from activation. The controller also monitors for an override condition and enables activation of the other of the humidification system or the dehumidification system accordingly.