“Does fresh air ventilation only occur when the Ultra-Aire dehumidifier is operating? Does the dehumidifier start and stop according to a humidistat? Can ventilation be controlled separately from dehumidification?”
The Ultra-Aire DEH3000 controller allows independent operation of the fresh air ventilation, air circulation, and dehumidification operating modes.
Dehumidification operates based upon a user set point input and an integrated or remote (DEH3000R) humidity sensor. Ventilation operates based upon a user programmed schedule (ASHRAE 62.2) and a user selectable duty cycle. Furthermore, ventilation will operate according to these settings while the dehumidifier will operate based upon the humidity sensor and user set point. Additionally, the Ultra-Aire DEH3000 also allows a manually selectable air circulation mode that will operate the fan continuously.
This leads to a number of possible operating modes:
Nothing – The humidity sensor is reading below the user set point and ventilation schedule is not calling for ventilation
Ventilating – Ventilating is based on the ventilation schedule with the humidity sensor reading below the user set point
Ventilating and dehumidifying – Ventilating based on the ventilation schedule with the humidity sensor reading above the user set point
Dehumidifying – The humidity sensor reads above the user set point and the ventilation schedule is not calling for ventilation