Desert Aire Aura QS, Installation And Operation Manual

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2.8.1 Duct-Mount Sensor
The duct-mount sensor is used in applications where continuous blower operation is
desired. A duct-mount sensor helps ensure consistent conditions throughout the
space. A drawback to this sensor is that it relies on a continuous stream of air moving
past it. Using a duct-mount sensor with a non-continuous blower may lead to
short-cycling of the refrigeration compressor.
2.8.2 Remote Room Sensor(s)
The remote room sensor is supplied with orders for the zone reset option. Up to four
of these sensors may be wired to the system using the standard control logic, if
additional sensors are required, please consult the factory.
2.8.3 CO
2
Sensors
The CO
2
sensors are supplied with orders for the CO
2
control package. The sensors
monitor the indoor and outdoor CO
2
levels. The measurements are used to determine
the CO
2
differential level in the conditioned space. This differential is the variable
compared to the CO
2
set point and is used in the control loop to provide more or less
outdoor air into the conditioned space.
2.9 Auxiliary Heating Control Wiring
Note: You must use the Desert Aire control system to control or interlock with the room heating
system. This prevents wide fluctuations in room air temperature. It also prevents the heater
from trying to heat the room while the dehumidifier is running in cooling.
2.9.1 Auxiliary Heating – Dry Contact Closure
Desert Aire will provide a dry contact closure to interlock with the building heating
system. This contact closure is normally used to interlock with a gas or electric duct
heater which has its own power supply transformer. When the room air temperature
drops below the set point, the dry contact will close to energize the auxiliary heater.
See the dehumidifier wiring diagram for details.
2.9.2 Auxiliary Heating – Proportional Signal
Desert Aire will provide a proportional signal to modulate a heating coil control valve
on units equipped with an integral heating coil.
This signal is reverse acting or direct acting depending on the settings in the controller.
It is critical that units with hot water or steam coils be set properly for freeze protection.
See controller manual for details on the settings and outputs.
Most proportional valves have either three or four terminals for field-installed wiring.
Desert Aire - QS/QV Manual