Navien NFC-175 Installation & Operation Manual page 99

11.4.6 Diagnosing the Boiler System
To run a series of test procedures for a system diagnosis, press the
Back button ( ) and the Menu button (
seconds, and then select "6. Test Mode".
Rotate the Command dial (
procedures. Press the Command dial (
Press the Back button ( ) to return to the previous screen or
menu.
Item
Test the fan operation by manually
changing the fan speed.
From a stopped state, the fan speed
●
gradually increases and reaches
1. Fan Motor the top speed, and then the fan
speed decreases until the fan stops
operating.
Rotate the Command dial (
●
or stop the fan test.
Test the boiler pump operation.
The boiler pump is turned on as soon
●
as you enter the test mode.
2. Boiler Pump
Press the Command dial (
●
toggle the pump operation (On ->
Off / Off -> On).
Test the Zone 1 pump operation.
The Zone 1 pump is turned on as
●
soon as you enter the test mode.
3. Zone 1 Pump
Press the Command dial (
●
toggle the pump operation (On ->
Off / Off -> On).
) simultaneously for 3
) to switch between the test
) to run a test procedure.
Description
) to run
) to
) to
Item
Test the zone 2 pump operation.
The zone 2 pump is turned on as
●
soon as you enter the test mode.
Press the Command dial (
●
4. Zone 2 Pump
toggle the pump operation (On ->
Off / Off -> On).
This option is available only when
●
the "Zone Pump System" is active.
Test the Zone 3 pump operation.
The Zone 3 pump is turned on as
●
soon as you enter the test mode.
5. Zone 3 Pump
Press the Command dial (
●
toggle the pump operation (On ->
Off / Off -> On).
Test the 3 Way valve operation.
The 3 Way valve is turned on as soon
●
as you enter the test mode.
6. 3 Way Valve Output
Press the Command dial (
●
toggle the valve operation (On -> Off
/ Off -> On).
Test the Flow control valve operation.
Rotate the valve from its current
position to fully open (0%), then fully
closed (100%) and then back to the
7. Flow Control Valve
starting position while checking
Output
feedback.
Display of the valve close ratio %
●
Display of "FEEDBACK" when
●
detecting the feedback
Test the Mixing valve operation. Rotate
the valve from its current position
to fully open (0%), then fully closed
(100%) and then back to the starting
8. Mixing Valve
position while checking feedback.
Output
Display of the valve close ratio %
●
Display of "FEEDBACK" when
●
detecting the feedback
Test the dual venturi operation.
The dual venturi is turned on as soon
●
as you enter the test mode.
9. Dual Venturi
Press the Command dial (
●
toggle the dual venturi operation (On
-> Off / Off -> On).
Test the recirculation pump.
The recirculation pump is turned on
●
as soon as you enter the test mode.
10. Recirc. Pump
Press the Command dial (
●
toggle the recirculation pump (On ->
Off / Off -> On).
Description
) to
) to
) to
) to
) to
Operating the Boiler 99