Navien NFC-175, Service Manual

Page: 46 / 138

46 NFC Service Manual
Version 1.0
Item Description
2. Cascade System
Removal
Select this option on the Main unit
of a cascade system to end cascade
operation.
●
Enter Cascade system setting mode
to reassign IDs and begin a cascade
system again.
●
If a Sub unit has a network
communication problem, select this
option on the Sub unit to exclude
the individual unit from the cascade
system.
3. Cascade Init-
operation Unit
Set the initial number of activated
boilers.
●
Setting range: 0 – 16
●
Default: 0
4. Cascade Protocol
Set the cascade protocol.
●
NPE or NR
●
Default : NPE
5. Number of Oper-
Unit
The number of units currently
operating in the cascade system.
6. Cascade Info.
View the operating status of individual
units in the cascade system.
7. Vent Type Setting
Set the type of ventilation.
●
Default: Common vent
4.9.4 Configuring a Cascade System
To view and configure the cascade settings, press the Back button
( ) and the Menu button ( ) simultaneously for 3 seconds,
and then select “4. Cascade Status and Set”.
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. Cascade System
Setting
●
To enter the Cascade Main setting
mode, select Start.
●
The setting mode is entered and
the IDs of all boilers that can
communicate with the Main via
the RS485 communication line are
initialized.
●
The boilers whose IDs are initialized
by the Main are set to <Sub setting
mode>, if you press the OK button
for 2 seconds or more, the Main gives
you the ID and it is displayed on the
screen.
●
The Main periodically checks the
RS485 communication, and when
there is an ID request from the Sub,
the ID is sequentially incremented
and added to the Sub (1 to 16).
●
Select OK in the Main to complete
the cascade setting, and the Main
and the assigned Sub IDs will return
to <Normal operation mode> and
turn into CASCADE ON state. At this
time, the Main icon on the Main
panel lights up.
●
If the cascade setting is idle for more
than 1 hour, it returns to <Normal
operation mode> and reverts to
CASCADE OFF state automatically.