Navien NCB-180 Service Manual page 34

c. Fully open a hot water fixture and set the boiler to
operate at 1-stage MIN mode (refer to page19 and
page 54). Measure the offset value at low fire and
compare it to the values in Table . If the offset value is
out of range, the gas valve set screw will need to be
adjusted.
If adjustment is necessary, locate the set screw as
shown in Figure 10. Using a 5/32" or 4mm Allen
wrench, turn the set screw no more than 1/4 turn
clockwise to raise or counterclockwise to lower the
offset value.
Figure 10
NOTE
The set screw is located behind the screw-on cover. This
must be removed first.
d. At high fire, do not check the offset value and never
adjust the gas valve.
DANGER
Improper gas valve settings can cause severe personal
injury, death or substantial property damage.
Once the CO or offset values have been confirmed, apply the
2
included conversion stickers to show that the appliance has
been converted to propane gas. Place this labels adjacent to
the rating plate as shown in Figure 11.
Figure 11. Proper Placement of Gas Conversion Labels