Navien NCB-24LSWE Service Manual page 55

Entering Test Information Mode
1. In <Normal operation mode> or <Error display mode>, press [ECO]+[Summer/Winter]+[S.H] for > 5 sec to access <Test
information mode>
2. Press [+] or [-] to navigate through the test information mode items.
3. Press [ECO] once to access the currently displayed mode.
Item
Error checking mode
Operation condition
setting mode.
Entering Error Checking Mode
1. In <Test Information mode>, press [+] or [-] and then press [ECO] once. <Error checking mode> opens and "1.TST" is
displayed on the front panel.
2. In <Error checking mode>, ensure the boiler and water circulation has stopped.
3. Change the component's values by pressing [+] or [-] to increase or decrease the settings.
4. Press [ECO] once. When "WAIT" is displayed start the component checks for the relevant item and then return to <Error
checking mode> after the checks end (3-way valve and dual venturi tests are excluded).
5. During the component checks, the tests are performed automatically (3-way valve and dual venturi tests are excluded).
6. The 3-way valve and dual venturi tests perform an ON / OFF operation by pressing [+] and [-]. If [Reset] is pressed or there is
no button activity for five minutes, the system returns to <Test information mode>.
7. Press [Reset] once to return to <Test information mode> or to the "1. TST" display.
8. If there is no button activity for five minutes, the system automatically returns to <Test information mode>.
Component
Fan motor
Pump
3-way valve
Dual venturi
Version 1.0
Description
Test that each device is operating normally.
Test the operational status of the DHW system.
Description
Fan motor test menu
Pump test menu
3-way valve test menu
Dual venturi test menu
Display
Display
NCB Service Manual 53