LG ARNU363DDA4 Installation Manual page 37

Table 11: Operating Issues and Concerns.
Issue or Concern
Outdoor temperature reading on the STATUS
menu is not accurate
If the enthalpy sensor drifts in accuracy over
time, can it be recalibrated?
Can I go back to factory defaults and start
over?
Will I be able to see the LCD screen when it is
in the unit?
What is a good setpoint for Mixed Air
Temperature (MAT)?
I am using enthalpy sensors. Why did the
control ask me to input a dry bulb changeover
temperature?
In checkout, the outdoor damper closes when I
command it to open.
How do I set my minimum position?
What if the damper does not completely close
in the checkout position?
How do I set the OCC?
Does the economizer save the program values
if the unit loses power?
If the unit is left in checkout, how long will the
unit stay in checkout mode without input?
Check the sensor wiring:
Enthalpy sensors are to be wired to the S-BUS terminals.
Temperature sensors are to be wired to the OAT and MAT terminals.
The sensor is not able to be recalibrated in the field. There is a menu item under the
ADVANCED menu, however, where it is possible to input a limited off set in temperature and
humidity for each sensor that is connected to the economizer.
The setpoints can be changed to the factory defaults under the SYSTEM SETUP menu.
The LCD screen has a backlight that is always illuminated.
The mixed air temperature is the temperature of air that you want to supply to the space. In a
commercial building, this is between 50°F to 55°F (10°C to 13°C). The mixed air is the mixing of
the return air and the outdoor air.
In the event the humidity sensor in the enthalpy sensor fails, the backup algorithm in the control
is to default to the temperature sensor in the enthalpy sensor.
Check the actuator linkage or rotation. In the CHECKOUT mode, the outdoor damper should
drive open to closed with the return air damper having the opposite effect.
Minimum position is set using VENTMIN and VENTMAX setup in the SETPOINTS menu.
VENTMIN is minimum ventilation required when using an occupancy sensor, and VENTMAX is
minimum ventilation when not using an occupancy sensor for Demand Control Ventilation.
VENMAX position is set the same as with the potentiometer on the analog economizer and is
the output voltage to the damper actuator. The range is 2 VDC closed OA damper and 10 VDC
open OA damper.
Check the damper linkage or hub to make sure the damper is able to closed completely.
There are two settings for the OCC setting: INPUT and ALWAYS. INPUT is from the space
thermostat, if it has an occupancy output. ALWAYS is the unit in the occupied mode, if the
economizer is powered (fan on).
Yes, once the changes are stored in the controller, they will be stored until changed by the
operator.
The unit will remain in checkout for ten (10) minutes, then return to normal operation.
Due to our policy of continuous product innovation, some specifications may change without notification.
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TROUBLESHOOTING
Possible Cause and Solution
37