Economizer Operation; Figure 57 Economizer Setup A2 - Bard FUSION-TEC WR36BPA Service Instructions Manual

4. Press UP or DOWN keys to scroll to Alarm Setup
A5.
5. Press ENTER key to scroll to Lo and Diff value (see
Figure 56 on page 33).
6. Press UP or DOWN keys to change the differential
to the desired value.
7. Press ENTER key to save value and scroll to Delay.
8. Press UP or DOWN keys to adjust the delay value.
NOTE: This delay is also applied to the high supply air
temperature alarm.
9. Press ENTER key to save.

Economizer Operation

The economizer has four types of operation. The first
mode is "None" where the economizer is never utilized,
except for emergency purposes. The second mode is
"Dry Bulb" where the outdoor temperature is the only
consideration for economizer use on a free cooling
call. The third mode is "TempHum" where the outdoor
temperature and humidity are considered for economizer
use on a free cooling call. The fourth mode is "Enthalpy"
where the outdoor temperature, humidity and calculated
dew point are considered for economizer operation on a
free cooling call.
To change the economizer type and setpoints:
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 Control Type (see
Figure 57).
6. Press UP or DOWN keys to change the Type
desired value to None, Dry Bulb, TempHum or
Enthalpy.
7. Press ENTER key to save the value and scroll to
the next parameter.
FIGURE 57
Economizer Setup A2
Manual 2100-695
Page 34 of 54
NOTE: Some of the following parameters may not be
present until the control type that it is used with
is selected.
8. If control type is other than None, the cursor
should now be on the OD Temp Set parameter.
9. Press UP or DOWN keys to change the parameter
to the desired value.
10. Press ENTER key to save the value and scroll to
the next parameter.
11. Press UP or DOWN keys to change the (outdoor
temperature) Off Diff parameter to the desired
value.
12. Press ENTER key to save the value and move to
the next parameter.
13. If control type is TempHum or Enthalpy, the cursor
should now be on Humidity Set parameter.
14. Press UP or DOWN keys to change the parameter
to the desired value.
16. Press UP or DOWN keys to change the (outdoor
humidity) On Diff parameter to the desired value.
17. Press ENTER key to save the value and move to
the next parameter.
18. If control type is Enthalpy, the cursor should now
be on Dew Pt Set parameter.
19. Press UP or DOWN keys to change the parameter
to the desired value.
20. Press ENTER key to save the value and move to
the next parameter.
21. Press UP or DOWN keys to change the (outdoor
dew point) On Diff parameter to the desired value.
22. Press ENTER key to save the value.
To change economizer settings:
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 A3.
5. Press ENTER key to scroll to Mixed Air Temp (see
Figure 58).
6. Press UP or DOWN keys to change the parameter
to the desired value.
7. Press ENTER key to save the value and move to
the next parameter.
8. Press UP or DOWN keys to change the
(economizer) Delay parameter to the desired value.
9. Press ENTER key to save the value.