Navien CH-180, Service Manual, Page: 135 / 155

© Navien Ameri c a I n c . 20 1 0 CH series servi c e Manua l Version 1 .0
8.2.14. 3-way Valve
1. Turn off the gas supply.
2. Turn off the 120V power supply.
3. Turn off the water supply. Drain all
water(include heating water) from
the appliance.
4. Remove the four screws securing
the front panel. Remove front panel.
5. Pull out the PCB. (refer to 8.2.1
PCB)
6. Pull out the circulation pump. (refer
to 8.2.13 Circulation Pump)
7. Loosen the heating water inlet pipe II
screw from 3-way valve.
17. Tighten the 4 screw from bottom
base.
18. Close the drain plug.
19. Replace the PCB. (refer to 8.2.1
PCB)
20. Install front panel using 4(four)
screws.
21. Turn on water supply, power
supply, and gas supply.
22. Check the operating circulation
pump and ensure there are no
leaks at the space heating piping
system inside the unit.
23. Open air vent on top of pump to
release air
8. Remove the stainless clip. (fastener “L-1”)
9. Loosen the heating adaptor 2 screw
from bottom base.
10. Pull out the 3-way
133
Figure 39
Figure 40
NOTE
1. Always use right part(O-ring) and
right size and place to pipe
2. Place black gasket ring on top of
the circulation pump and screw on
the stainless nut; be sure not to
cross thread; over tightening may
damage gasket