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108 Operating the Boiler
Item
Description
5. SH Burner Off Diff
Set the temperature
range to turn off space
heating.
●
Setting range: 2°F (1°C)
– 54°F (30°C)
●
Default: 4°F (2°C)
6. SH Burner On Diff
Set the temperature
range to turn on space
heating.
●
Setting range: - 2°F
(1°C) – 54°F (30°C)
●
Default: 5°F (3°C)
7. SH Min Limit
Set space heating
minimum heat capacity
limit.
●
Setting range: Space
heating Min capacity
(%) – [space heating min
capacity limit -20]) %
●
Default: Boiler’s
minimum heat capacity
8. SH Max Limit
Set space heating
maximum heat capacity
limit.
●
Setting range: (Space
heating Min capacity
limit +20) % – 100%
●
Default: 100%
9. SH Min Burning
Time
Set the low-load
combustion time at initial
operation.
●
Setting range: 1 – 20
min
●
Default: 1 min
10. Burning
Acceleration Time
Set the time to reach the
maximum space heating
capacity after initial
operation.
●
Setting range: 0 – 20
min
●
Default: 1 min
11. Zone T/S Start-
up Delay Time
Set the delay time for the
burner to operate after a
call for heat is received for
the AHU.
●
Setting range: 0–120 sec
●
Default: 0 min
In the password screen, rotate the Command dial
(
) to change numbers and places, and press the
Command dial (
) to enter the password.
The factory default password is “1234”.
After entering the parameter setting screen, rotate
the Command dial (
) to switch between the
parameters or to increase/decrease setting values.
Press the Command dial (
) to select a parameter
or to confirm after making changes.
Press the Back button (
) to return to the previous
screen or menu.
Item
Description
1. Supply MIN Set-
point
Set the space heating
supply minimum
temperature.
●
Setting range: 77°F
(25°C) – [MAX Set-point
– 36°F (20°C)]
●
Default: 104°F (40°C)
2. Supply MAX Set-
point
Set the space heating
supply maximum
temperature.
●
Setting range: [MIN
Set-point + 36°F (20°C)]
- 190°F (88°C)
●
Default: 180°F (82°C)
3. Return MIN Set-
point
Set the space heating
return minimum
temperature.
●
Setting range: 68°F
(20°C) – [MAX Set-point
– 18°F (10°C)]
●
Default: 86°F (30°C)
4. Return MAX Set-
point
Set the space heating
return maximum
temperature.
●
Setting range: [MIN
Set-point + 18°F (10°C)]
– 158°F (70°C)
●
Default: 149°F (65°C)
Summary of Contents for NFB-175H
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