Manual 2100-694B
Page
34 of 62
15. Press UP or DOWN keys to change the parameter
to the desired value.
16. Press ENTER key to save the value and move to
the next parameter.
17. The cursor should now be on
On Diff
(Outdoor
Humidity On Differential) parameter.
18. Press UP or DOWN keys to change the parameter
to the desired value.
19. Press ENTER key to save the value and move to
the next parameter.
20. The cursor should now be on the
Dew Pt Set
(Dew
Point Setpoint) parameter.
21. Press UP or DOWN keys to change the parameter
to the desired value.
22. Press ENTER key to save the value and move to
the next parameter.
23. The cursor should now be on the
On Diff
(Dew
Point On Differential) parameter.
24. Press UP or DOWN keys to change the parameter
to the desired value.
25. Press ENTER key to save the value and continue
pressing ENTER until blinking cursor is on the
page number at the top right of screen.
26. Press UP or DOWN keys to scroll to
Economizer
Setup A3
(see Figure 53).
27. Press ENTER key to move cursor to the
Mixed Air
Temp
parameter.
28. Press UP or DOWN keys to change the parameter
to the desired value.
NOTE:
The mixed air temperature setpoint is for
economizer only freecooling; the mixed air
setpoint is raised during optimized cooling to
prevent the evaporator from getting too cold.
29. Press ENTER key to save the value and move to
the next parameter.
30. The cursor should now be on the
Econ Off Delay
parameter.
31. Press UP or DOWN keys to change the parameter
to the desired value.
32. Press ENTER key to save the value.
See Table 11 for default settings for economizer
operation.
When the economizer is activated during a freecooling
call only, using any of the previously mentioned modes,
a 0-10v analog signal will be sent to the economizer
actuator. Regardless of economizer only, or optimized
cooling mode, the actuator will then open and close the
damper blades to maintain a supply air temperature of
55°F. During optimized cooling mode, the damper blades
will be limited to a max output of 60%. When the supply/
mixed air temperature increases, the damper will open
and when the mixed air temperature decreases, the
damper will close.
The economizer may be disabled by the LV if the system
determines it needs to enter dehumidification mode.
More information about the dehumidification sequence
can be found on page 16 and in the latest revision of
LV1000 Service Instructions 2100-673. 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.
TABLE 11
Economizer Default Settings
* In Enthalpy mode, outdoor temperature, humidity and calculated dew point are all considered for economizer operation.
Mode
Consideration
Economizer Available for Cooling
Economizer Not Available for Cooling
Temp
Only
Temp & Humidity
Enthalpy*
Temperature
When the outdoor air temperature
is below 70°F
When the outdoor air temperature
is above 75°F
Humidity
LV Online
: When the outdoor humidity
is below 80%
LV Online
: When the outdoor humidity
is above 80%
LV Offline
: When the outdoor humidity
is below 60%
LV Offline
: When the outdoor humidity
is above 60%
Dew Point
When the outdoor dew point
is below 55°F
When the outdoor dew point
is above 60°F
FIGURE 53
Economizer Setup A3
