High Supply Air Temperature Alarm; Low Supply Air Temperature Alarm; Economizer Operation; Figure 56 Adjusting Supply Air Temperature Differential - Bard FUSION-TEC WR35BPA Service Instructions Manual

High Supply Air Temperature Alarm

When the supply air temperature is above 80°F for
120 seconds, an alarm will be generated and the
economizer will be disabled until the cooling call has
been removed. This alarm can only be activated during
free cooling and will automatically reset once the
economizer is no longer disabled.
To change the high supply air temperature alarm:
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 Alarm Setup A5.
5. Press ENTER key to scroll to Hi and Diff value (see
Figure 56).
6. Press UP or DOWN keys to change the differential
to the desired value.
7. Press ENTER key to save the value.
FIGURE 56
Adjusting Supply Air Temperature Differential

Low Supply Air Temperature Alarm

When the supply air temperature is below 45°F for
120 seconds, an alarm will be generated and the
economizer will be disabled until the cooling call has
been removed. This alarm can only be activated during
free cooling and will automatically reset once the
economizer is no longer disabled..
To change the low supply air temperature alarm:
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 Alarm Setup
A5.
5. Press ENTER key to scroll to Lo and Diff value (see
Figure 56).
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).
FIGURE 57
Economizer Setup A2
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.
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.
Manual 2100-695C
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