Navien NFC-175, Installation & Operation Manual

Page: 96 / 124

96 Operating the Boiler
Item Description
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. Anti Fast Cycling
Time*
Set the anti-fast cycling time.
●
Setting range: 0 – 20 min
●
Default: 3 min
12. DHW Min Limit
Set the DHW supply minimum
temperature.
●
Setting range: DHW minimum
capacity (%) – [DHW MAX capacity
limit - 20] %
●
Default: Boiler’s minimum heat
capacity
13. DHW Max Limit
Set the DHW supply maximum
temperature.
●
Setting range: [DHW Min capacity
limit + 20] % – 100%
●
Default: 100%
14. Freeze protection
Set the pump freeze protection
temperature.
●
Setting range: 43°F (6°C) – 50°F (10°C)
●
Default: 50°F (10°C)
Note
The system freeze protection
temperature is set based on
the pump freeze protection
temperature.
15. Auto-Fill Pressure
Set the Auto-Fill Pressure.
●
Setting range: 12 - 50 psi
●
Default: 12 psi
16. High Sys Pressure
Set the high system water pressure.
●
Setting range: 40 – 80 psi
●
Default: 50 psi
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)] – 194°F (90°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)
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