3-Way Valve - Navien NCB-150E Service Manual

10. Secure the pump with the stainless steel clip and the 2 fixing
screws.
11. Reinstall the pump drain plug at the bottom of the unit.
12. Reconnect the wiring connector at the pump.
13. Install the Main PCB back onto the unit by using the four
screws.
14. Turn on water supply, power supply, and gas supply to the
unit.
15. Open a hot water tap and ensure that there are no leaks at the
pump connections.
16. Open the air vent on top of pump to release air within the
system.
142 NCB-E Service Manual
Figure 28
Figure 29
NOTE
Always use proper O-rings at the pump connection to ensure
tight seals

6.2.11 3-way Valve

1. Turn off the gas supply to the unit.
2. Turn off the 120V power supply to the unit.
3. Turn off the water supply to the unit. Drain all water from the
appliance.
4. Remove the Circulation Pump (see page 137)
5. Remove the fastener and two screws on the 3-way valve.
Figure 30
6. Remove the two screws on the bottom of case.
Figure 31
Version 1.4