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100 Operating the Boiler
Item
Description
5. AHU SH Set Temp
Note
Use with iFlow Air
Handlers Only.
AHU Space Heating Set
Temperature (°F)
●
If AHU is not connected,
“--” will be displayed.
●
The temperature is
displayed by 1 degree
increments for Fahrenheit
and by 0.5 degree
increments for Celsius.
This is due to the degree
control specifications of
0.5 degree for the AHU
communication type.
6. Supply Temp
Heating supply
temperature (°F)
7. Return Temp
Boiler return temperature
(°F)
8. Sys Supply Temp
System supply
temperature (°F)
9. Sys Return Temp
System return
temperature (°F)
10. Outdoor Temp
Outdoor temperature (°F)
11. Approx. Boiler
Flow
Flow rate (GPM)
12. DHW Tank set
Temp
DHW Tank set temperature
(°F)
13. Tank Sensor
Temp
DHW indirect tank
temperature (°F)
14. Water Press
Water pressure (psi)
15. Flame Value
Flame detector AD value
●
Flame On: 8bit AD
values equal to or lower
than 70
●
Flame Off: 8bit AD
values equal to or
higher than 175
16. Fan Target RPM
Set fan speed (RPM)
17. Fan Current RPM
Fan speed (RPM)
18. Fan Target APS
Set APS voltage (V)
19. Fan Current APS
APS voltage (V)
20. Exhaust Temp
Exhaust temperature (°F)
21. Outdoor Reset
Outdoor reset status
(Enable / Disable)
11.5 Accessing Basic Menu Items
In the Menu Select screen, you can view the boiler’s
operating conditions, configure the space heating
and DHW temperatures, and review error history.
Press the Menu button (
) to enter the Menu
Select screen.
11.5.1 Viewing Basic Information
To view information about the boiler, press the
Menu button (
), and then select “1. Status
Information”.
Rotate the Command dial (
) to switch between
the information items. Press the Command dial (
)
to select an item and view the information.
Press the Back button (
) to exit information view
mode.
Item
Description
1. Operation State
Current Operation State
2. Heat Capacity
Heat Capacity (%)
3. SH Set Temp
Space heating set
temperature (°F)
4. DHW Set Temp
DHW indirect supply set
temperature (°F)
Summary of Contents for NFB-175H
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