Benchmark 750-3000 Installation & Startup Manual
SECTION 4
– INITIAL START-UP
OMM-115_D
•
GF-200
•
5/9/2019
Technical Support
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4.7.1 Digital Alarm Switch Checks and Adjustments
The
Over-Temperature Alarm
switch settings can be checked or adjusted using the controls
and display on the front panel of the switch illustrated and described in Figure 4-7 and
Table 4-9.
F
Alarm
RST
SET
Limit Control
Figure 4-7: Digital Over-Temperature Alarm Switch Front Panel
TABLE 4-9: Over-Temperature Alarm Switch Controls and Display
CONTROL/DISPLAY
MEANING
FUNCTION
LED Display
TEMP status
Displays current water temperature or setpoint.
RST
RESET Button Resets the unit after an alarm condition.
UP Button
Increases the displayed temperature.
DOWN Button
Decreases the displayed temperature.
SET
SET Button
Used to access and store parameters in the unit.
Perform the following steps to check or adjust the
Over-Temperature Alarm
switch settings:
Over-Temp Alarm Switch Check and Adjustment Instructions
1.
Set the ON/OFF switch to the
ON
position.
2.
Press the
SET
button on the
Over-Temperature Alarm
switch.
SP
will appear in the
display.
3.
Press the
SET
button again. The current over-temperature limit value stored in memory will
be displayed. (Default = 210°F, 98.9
°C
).
4.
If the display does not show the required over-
temperature alarm setting, press the ▲ or ▼
arrow button to change the display to the desired temperature setting.
5.
Once the desired over-temperature alarm setting (210ºF) is displayed, press the
SET
button to store the setting in memory.
6.
To calibrate the offset (P1), press and hold the
SET
button on the Over-Temperature Alarm
switch for 8 seconds. Access code value
0
should appear in the display. The switch comes
from the factory with the code set at 0. AERCO recommends that you do not change this
code.
7.
Press the
SET
button again to enter the code.
The first parameter label,
SP
,
will appear in
the display.
8.
Using the ▲ and ▼ arrow keys, select parameter P1.
9.
Press
SET
to view the value stored in memory.
10.
If the desired value is not displayed, modify the setting using the ▲ and ▼ arrow keys. The
value can be changed from -10° to +10° (-5.5
°C
to + 5.5
°C)
offset. Press
SET
to enter the
value and exit to the text parameter.
11.
To exit the programming mode, press the
SET
and ▼ buttons simultaneously or simply
wait one minute and the display will automatically exit the programming mode.
12.
Once the programming mode has been exited, the display will show the current outlet
water temperature of the boiler.