Navien NPE-180A2 Installation Manual page 105

d. Fully open several hot water fixtures and set
the water heater to operate at 2-stage MAX
mode (refer to "Setting the Operation Mode"
on page 105). Measure the CO
high fire.
If the CO values do not match Table 2 at
2
high fire, do not adjust the gas valve. Check
for the proper Gas Orifice.
DANGER
Improper gas valve settings can cause severe
personal injury, death or substantial property
damage.
Option 2. Using Digital Manometer
a. Open the offset pressure port by loosening
the screw two turns as shown in Figure 9.
Figure 9
b. Connect a manometer to the offset pressure
port. For dual port manometers, use the
positive pressure side.
Model Altitude Kit Part No.
0 - 5,399 ft NAC-N150
5,400 -
NPE- NAC-NH150
10,100 ft
150S2
0 - 10,100 ft NAC-L150
0 - 5,399 ft NAC-N180
NPE-
5,400 -
180A2 NAC-NH180
10,100 ft
NPE-
180S2
0 - 10,100 ft NAC-L180
104 Appendixes
value at
2
Gas
Offset
Type
Natural -0.04 in
Gas ± 0.01 in
Propane -0.03 in
Gas ± 0.01 in
Natural -0.03 in
Gas ± 0.01 in
Propane -0.02 in
Gas ± 0.01 in
Model Altitude Kit Part No.
0 - 5,399 ft NAC-N210
NPE-
5,400 -
210A2 NAC-NH210
10,100 ft
NPE-
210S2
0 - 10,100 ft NAC-L210
0 - 5,399 ft NAC-N240
NPE-
5,400 -
240A2 NAC-NH240
10,100 ft
NPE-
240S2
0 - 10,100 ft NAC-L240
Table 3. Offset value for low fire
c. Fully open a hot water fixture and set the
water heater to operate at 1-stage MIN
mode (refer to "Setting the Operation Mode"
on page 105). Measure the offset value at
low fire and compare it to the values in Table
3. 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
or 4 mm Allen wrench, turn the set screw
no more than / turn clockwise to raise or
1
4
counterclockwise to lower the offset value.
Figure 10
The set screw is located behind
Note
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.
Gas
Offset
Type
Natural -0.03 in
Gas ± 0.01 in
Propane -0.02 in
Gas ± 0.01 in
Natural -0.03 in
Gas ± 0.01 in
Propane -0.02 in
Gas ± 0.01 in
/ in
5
32