Economizer Operation - Minimum Position; Miscellaneous Components; Supply Temperature Sensor; Figure 58 Supply Air Temperature Sensor - Bard MEGA-TEC W180B Service Instructions Manual

Mode Consideration
Temperature
Humidity
Dew Point
* In Enthalpy mode, outdoor temperature, humidity and calculated dew point are all considered for economizer operation.
sequence can be found in the latest revision of LC6000
Service Instructions 2100-669. In addition to dehum
mode, the economizer may be disabled for 5 minutes
(adjustable) if the dust sensor indicates the outdoor
air may cause particulate buildup in the air filters.
After the time has expired and on a call for cooling,
the economizer will open again to sample the air. The
wall-mount unit will either return to normal operation
or remain locked out for another 5 minutes.
Economizer Operation – Minimum Position
The economizer has an option to set minimum position
for the economizer. The minimum position will only
be active while the blower is operating. To enable
minimum position all the time, continuous blower must
be activated for the wall unit in the LC6000. See latest
version of LC6000 Service Instructions 2100-669 for
continuous blower configuration.
To set the minimum position value:
1. Press MENU key to go to the Main Menu screen.
2. Press UP or DOWN keys and ENTER key to enter
USER password 2000.
3. Press UP or DOWN keys to scroll to System Config;
press ENTER key.
4. Press UP or DOWN keys to scroll to Economizer
Setup A2.
5. Press ENTER key to scroll to Min Position (see
Figure 54 on page 34).
6. Press UP or DOWN keys to change to the desired
value.

Miscellaneous Components

Supply Temperature Sensor

The unit is equipped with two supply air temperature
sensors, located in the supply opening of each air path,
to monitor the leaving air temperature of the unit.
The temperature is measured with a 10k ohm NTC
thermistor.
The supply air temperature can be verified by:
1. Press MENU key to go to the Main Menu screen.
Manual 2100-749
Page 36 of 68
TABLE 11
Economizer Default Settings
Economizer Available for Cooling
When the outdoor air temperature
is below 70°F
When the outdoor humidity is below
80%
When the outdoor dew point
is below 55°F
2. Press UP or DOWN keys and ENTER key to enter
TECHNICIAN password 1313.
3. Press UP or DOWN keys to scroll to I/O Config;
press ENTER key.
4. Press UP or DOWN keys to scroll to Analog Inputs;
press ENTER key.
5. Press UP or DOWN keys to scroll to Analog Ins
C3-2 (Supply Air Temp 1) or C3-3 (Supply Air
Temp 2).
6. Reference the Value to see the input of the sensor
(see Figure 58).
7. To apply an offset, press ENTER key to scroll to
Offset.
8. Press UP or DOWN keys to change to the desired
value.
9. Press ENTER key to save the value.
Economizer Not Available for Cooling
When the outdoor air temperature
is above 75°F
When the outdoor humidity is above
80%
When the outdoor dew point
is above 60°F
FIGURE 58
Supply Air Temperature Sensor