Navien NFB-175 Mode D'emploi page 87

Item
Set the boost interval time.
3-6. Boost Interval
Setting range: 0 – 120 min
●
Time***
Default: 0 min
●
Enable or disable heating zones utilizing
the Navien Zone Controller.
4. Navien zone cont.
Setting range: Enabled/Disabled
●
Default: Disabled
●
Select a heating control type.
1: Supply Temperature
2: Return Temperature
5. SH Control
3: Sys Supply Temperature
Method
4: Sys Return Temperature
Default: Supply Temperature
●
* Available only when "2. Outdoor Reset ON/OFF" is set to "Enabled".
** A preset or user defined temperature range is set automatically based on
the curve selected. Refer to the settings table for details.
Supply Set
Heat Load
Point Range
1. Finned Tube 120–180°F
Baseboard (48.5–82°C)
140–180°F
2. Fan Coil
(60–82°C)
3. Cast Iron 100–170°F
Baseboard (37.5–76.5°C)
4. Low Mass 80–140°F
Radiant (26.5–60°C)
5. High Mass 80–120°F
Radiant (26.5–48.5°C)
120–170°F
6. Radiators
(48.5–76.5°C)
104–180°F
7. Custom
(40–82°C)
Heat loads 1-6 show the preset temperature ranges based on the load
type selected, while heat load 7 provides a custom temperature range.
When the custom temperature range is in use, the boiler operates based
on the user–defined "Absolute Min" and Absolute Max" temperature
settings.
*** The boost interval time may be set to prevent interruption in space
heating while using the Outdoor Reset Control mode, due to changes
in heat load conditions. With the boost interval time enabled, the boiler
increases the space heating supply temperature by 9°F (5°C) and the
return temperature by 5°F (3°C) after a set time elapses.
CAUTION
An outdoor sensor error may occur if the Outdoor Reset
Control mode is enabled without the outdoor sensor installed
Description
Return Set
Remarks
Point Range
101–147°F
Default
(38–63.5°C)
116–147°F
(46.5–63.5°C)
86–139°F
(30–59°C)
70–116°F
(21–46.5°C)
70–101°F
(21–38°C)
101–139°F
(38–59°C)
86–149°F User-
(30–65°C) defined
In the Outdoor Reset Control mode, the boiler's water
Note
temperature is regulated according to the outdoor
temperature to maximize boiler efficiency and reduce
energy usage. This mode must remain enabled and
the outdoor sensor must be installed to comply with
federal efficiency regulations. The Outdoor Reset mode
may only be disabled if the boiler is not used for any
space heating.
11.3.4 Setting the DHW Operation (Indirect)
To set the boiler's indirect DHW operation, press the Menu button
( ), and then select "4. DHW Operation".
Rotate the Command dial (
to increase/decrease setting values. Press the Command dial (
to select an item or to confirm after making changes.
Press the Back button ( ) to return to the previous screen or
menu.
Item
Set the external hot water tank
temperature (°F).
Setting range: 86
●
Default: 122°F (50°C)
1. DHW Tank Set ●
This option is available only when a
Temp
tank temperature sensor is connected
to the boiler, and only when "3. DHW
Call Signal" is set to "2. DHW Tank
Sensor".
Set DHW Thermostat Temperature.
Setting range: 104
●
Default: 180°F (82°C)
●
2. DHW Boiler Set
Set DHW Tank Sensor Temperature.
Temp
Setting range: [DHW Tank Set Temp
●
+ 18°F (10°C)] – 194°F (90°C)
Default: 180°F (82°C)
●
) to switch between the list items or
Description
149°F (30 65°C)
– –
180°F (40 82°C)
– –
Operating the Boiler
)
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