DANGER
When conversion is required, be sure to set the Front Panel DIP
switches according to the supply gas type.
Failure to properly set the DIP switches could cause carbon monoxide
poisoning, resulting in severe personal injury or death.
11. Measure and adjust the gas/air ratio.
Option 1. Using Combustion Analyzer (recommended)
a. Loosen the screw, rotate the plate and remove the gasket
to access the emissions monitoring port as shown in Figure 7.
b. Insert the analyzer into the port (Figure 7).
Figure 7
Table 2. CO
2
value
(CO
2
values must be within 0.5% of the values listed.)
c. Fully open several hot water fixtures and set the water
heater to operate at 1-stage MIN mode (refer to page 8).
Measure the CO
2
value at low fire.
If the CO
2
value is not within 0.5% of the value listed in
Table 2, the gas valve set screw will need to be adjusted.
If adjustment is necessary, locate the set screw as shown
in Figure 8. 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 CO
2
value.
Water
Heater
Fuel
High fire
Low fire
%CO
2
%CO
2
NPE-180A
NPE-180S
NG
8.9
9.5
LP
10.2
10.8
NPE-210A
NPE-210S
NG
8.9
9.5
LP
10.2
10.8
NPE-240A
NPE-240S
NG
8.9
9.5
LP
10.2
10.8
b.
Connect a manometer to the offset pressure port. For
dual port manometers, use the positive pressure side.
Model
Kit Part No.
Gas Type
Offset
NPE-180A
NPE-180S
NAC-01
LP
-0.03"±0.01"
NAC-100
NG
-0.04"±0.01"
NPE-210A
NPE-210S
NAC-02
LP
-0.02"±0.01"
NAC-200
NG
-0.04"±0.01"
NPE-240A
NPE-240S
NAC-03
LP
-0.02"±0.01"
NAC-300
NG
-0.04"±0.01"
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 page 8).
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 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
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.
Figure 8. Set Screw Location
The set screw is located behind the screw-on cover.
This must be removed first.
d. Fully open several hot water fixtures and set the water heater to
operate at 2-stage MAX mode (refer to page 8). Measure the CO
2
value at high fire.
If the CO
2
values do not match Table 2 at 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
12.
Once the CO
2
or offset values have been confirmed, apply
the included conversion stickers to show that the appliance
has been converted to propane gas. Place these labels
adjacent to the rating plate as shown in Figure 11.
Figure 11. Proper Placement of Gas Conversion Labels
Manifold Gas Pressure ratings can change due to
updated orifice sizes. Please confirm new
manifold pressures approved by CSA before
production of gas conversion labels.
Setting the Operation Mode
1.
Using the Front Panel, press and hold the Diagnostics Button for
over 5 seconds until “1.TST” is displayed.
2.
Press the + (Up) button once to change the display to“2.OPR”.
3.
Press the Information Button once to access the Operation Mode
menu.
4.
Press the + (Up) button once to set the water heater to operate at 1-
stage MIN (“MIN.1”).
5.
To set the water heater to operate at 2-stage MAX, press the (Up)
button 3 times or until“MAX.2” is displayed.
6.
To exit the Operation Mode and return the water heater to normal
operation, press the Reset button twice.
Diagnostics
Information
Reset
Navien America, Inc.
20 Goodyear lrvine, CA 92618
TEL +949-420-0420 FAX +949-420-0430
www.navienamerica.com
