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120 Operating the Boiler
Item
Description
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)
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
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.
●
[Supply MIN Set-point + 36°F
(20°C)] – 185°F (85°C)
●
Default: 180°F (82°C)
Summary of Contents for NFC-250/175H
Page 67: ...67 Venting for Combustion Air WARNING The vent installation detector Detectable Undetectable...
Page 149: ...Memo...
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