Navien NFC-250/175H Installation Manual page 121

Item
Set the delay time for the burner
to operate when there is a call for
11. Zone
heat for a zone valve.
T/S Start-up
Delay Time Setting range: 0–120 sec
●
Default: 0 min
●
Set the anti-fast cycling time.
12. Anti
Fast Cycling Setting range: 0 – 20 min
●
Time*
Default: 3 min
●
Set the DHW minimum heat
capacity.
Setting range: DHW minimum
●
13. DHW Min
capacity (%) – [DHW MAX
Limit
capacity limit - 20] %
Default: Boiler's minimum heat
●
capacity
Set the DHW maximum heat
capacity.
14. DHW Max
Setting range: [DHW Min
●
Limit
capacity limit + 20] % – 100%
Default: 100%
●
Set the pump freeze protection
temperature.
Setting range: 43°F (6°C) – 50°F
●
(10°C)
Default: 50°F (10°C)
●
15. Freeze
Note
protection
Set the Auto-Fill Pressure.
16. Auto-Fill
Setting range: 12 – 50 psi (0.8
●
Pressure
– 3.4 bar)
Default: 12 psi (0.8 bar)
●
Set the high system water
pressure.
Setting range: [Auto-Fill
●
Pressure + 10 psi] – 80 psi
([Auto-Fill Pressure + 0.6bar] –
17. High Sys
Pressure 5.5 bar)
Note
Default: 50 psi (3.4 bar)
●
Description
The boiler pump will
operate to provide
system freeze protection
when the water
temperature falls below
this value.
The high system water
pressure cannot be set
lower than 40 psi (2.7 bar).
Item
Set the space heating pump
18. Boiler
over-run time.
Pump
Setting range: 3 – 40 min
●
Delay**
Default: 40 min
●
Set the DHW wait time.
19. DHW
Setting range: 0 – 20 min
●
Wait Time
Default: 3 min
●
Set the recirculation or HotButton
operation time.
20. Recirc.
Interval Time
Setting range: 1 – 120 min
●
Default: 20 min
●
Set the recirculation interval time.
21. Recirc.
Sampling
Setting range: 1 – 120 min
●
Time
Default: 30 min
●
Set the temperature range to
turn off
recirculation or HotButton
22. Recirc. Off
operation.
Diff. Temp
Setting range: 5°F (3°C) – 54°F
●
(30°C)
Default: 9°F (5°C)
●
Set On-Demand recirculation to
activate according to pipe length
when HotButton is installed, and
Thermal Bypass and external
23. Fixture
surface thermometer is disabled.
Dist.
(HotButton)
Setting range: 15 ft (4.5 m)
●
– 660 ft (198 m) (5 ft (1.5 m)
intervals)
Default: 30 ft (9 m)
●
Enable or disable the gas
connection error detection
24. Gas
function.
Connect
Error Check
Setting range: Enable or
●
Enable
disable
Default: Enable
●
Set the time for service
notification.
Setting range: 30 – 3650 days
●
25. Service
(10 years)
Notif Time
It can be set in 10 day
●
increments.
Default: 1820 days (5 years)
●
Description
Operating the Boiler 121