Dehumidification Mode: Duct Static Pressure

When the space humidity rises above the setpoint, a PreciseLine in Dehumidification Mode with Single Zone VAV fan controls selected will activate the cooling coil controlled to a leaving coil temperature and the reheat coil controlled to the space temperature setpoint.

As VAV boxes close, the pressure in the system rises. This causes the fan to reduce speed in order to maintain a constant supply duct pressure.