Navien NCB-180 User manual

Combination Boiler
Model
NCB-180/210/240
This boiler is configured for Natural Gas
from the factory. If conversion
to Propane Gas is required, the
conversion kit supplied with the boiler
must be used.
WARNING
This conversion kit shall be installed by a qualified service agency* in
accordance with Navien America’s instructions and all applicable codes and
requirements of the authority having jurisdiction. The information in these
instructions must be followed to minimize the risk of fire or explosion or to
prevent property damage, personal injury or death. The qualified service
agency is responsible for the proper installation of this kit. The installation is
not proper and complete until the operation of the converted appliance is
checked as specified in the manufacturer’s instructions supplied with the kit.
٭ A qualified service agency is any individual, firm, corporation or company
which either in person or through a representative is engaged in and is
responsible for the connection, utilization, repair or servicing of gas
utilization equipment or accessories; who is experienced in such work,
familiar with all precautions required, and has complied with all of the
requirements of the authority having jurisdiction.
In Canada
: The conversion shall be carried out in accordance with
the requirements of
the provincial authorities having jurisdiction
and in accordance with the requirements of the CAN
‐B149.1 and
CAN1‐B149.2 Installation Code.
Tools Required:

Phillips Screwdriver

Flathead Screwdriver

5/32 in or 4mm Allen Wrench

Combustion Analyzer or Dual Port Manometer

Gas Leak Detector
Included Items:

Gas Orifice (refer to below table)
Model
NG
LP
1STAGE
2STAGE
1STAGE
2STAGE
NCB-180
Ø4.80
Ø5.95
Ø3.80
Ø4.70
NCB-210 Ø6.10 Ø6.30 Ø4.50 Ø4.80
NCB-240
Ø6.10
Ø6.30
Ø4.50
Ø4.80
Table 1. Orifice Size

Gas Pressure and Conversion Kit Number Labels
11.
Once the Gas Orifice is exposed, remove the two screws that
hold the part in place. Remove the Gas Orifice from its housing
and prepare the new Gas Orifice for the LP conversion for
installation.
Figure 4. Access to Gas Orifice in Fan Assembly
WARNING

DO NOT adjust or attempt to measure gas valve outlet
pressure. The gas valve is factory-set for the correct outlet
pressure. This setting is suitable for natural gas and propane,
requiring no field adjustment.

Attempting to alter or measure the gas valve outlet pressure
could result in damage to the valve, causing potential severe
personal injury, death or substantial property damage. Navien
NCB boilers are shipped ready to fire natural gas ONLY.
Figure 5. Exploded View of Gas Pipe Assembly
DANGER
See Figure 5. Inspect the O-ring between the gas valve and gas valve inlet
adapter whenever they are disassembled. The O-
ring must be in good
condition and must be installed. Failure to comply will cause a gas leak,
resulting in severe personal injury or death.
Procedure:
1. Turn off both gas and water supply to the boiler.
2. Using a Phillips screwdriver, remove 4 screws (2 from the top and 2 from
the bottom) of the front cover assembly to gain access to the internal
components. See Figure 1 for illustration of the front cover on the unit.
3. Once the front cover is removed, place it in a safe location to prevent
accidental damage.
4. Label all the wires on the PCB.
5. Disconnect all the wires.
6. Loosen the three screws indicated in the figure. (Refer to Figure 2.)
7
. Remove the PCB assembly.
8
. With the internal components exposed, locate the gas inlet
pipe and the gas valve in the middle of the unit.
9.
Use a Phillips screwdriver to remove the two screws at location
A - the connection below the gas valve where it connects to the
pipe. See Figure 3 for reference. Once the screws are removed,
carefully separate the pipe from the gas valve.
10.
Once the gas inlet pipe is detached from the gas valve, find
location B - the connection above the gas valve where it is
attached to the fan motor assembly. Carefully remove the four
screws by hand using a Phillips screwdriver and pull the gas
valve away from the fan assembly to access the gas orifice.
Figure 3. Detaching Gas Valve from
Gas Inlet Pipe and Fan Motor Assembly
Figure 6. Orifice identification
12.
Replace the old Orifice piece with the new part for use with LP
gas. Ensure that the Orifice is properly seated inside the port
before proceeding to the next step.
13. Replace the gas inlet pipe to its original position and use all
screws to secure all connections.
Do not overtighten as this may damage or crack the
components.
DANGER
Inspect the O-ring between the gas valve and gas valve inlet adapter
whenever they are disassembled. The O-ring must be in good condition
and must be insta
lled. Failure to comply will cause a gas leak, resulting
in severe personal injury or death.
14. Place the PCB assembly back on to the boiler and tighten the
three screws.
15.
Check the labels carefully and then connect all the wires.
16.
Set the front panel Dip Switch to change the gas type. For LP, set Dip
Switch 2 #2 to On. For NG, set DIP SW2 #2 to Off.
WARNING
Ensure that you have turned off the power to the boiler before accessing the
DIP switches.
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.
17. Turn on the gas and water supply to the boiler.
Location B: Remove
4 screws here
Location A:
Remove
2 screws here
Figure 1.
Figure 2.
Gas Orifice
O
-ring
Remove two (2)
screws here

18. 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. Insert the Analyzer
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 boiler 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 in
or 4 mm Allen wrench, turn the set screw no more than
1/4 turn clockwise to raise or counterclockwise to lower
the CO
2
value.
Model Fuel
High fire
Low fire
%CO
2
%CO
2
NCB-180
NG
8.9
9.5
LP
10.2
10.8
NCB-210
NG
8.9
9.5
LP
10.2
10.8
NCB-240
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
NCB-180
NAC-01
LP
-0.03"±0.01"
NAC-100
NG
-0.04"±0.01"
NCB-210
NAC-02
LP
-0.02"±0.01"
NAC-200
NG
-0.04"±0.01"
NCB-240
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 boiler to
operate at 1-stage MIN mode (refer to table 2). 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 boiler to operate at
2-stage D. 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. Connect Digital Pressure Monometer
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 or over 5
seconds until “1.PAR” is displayed.
2.
Press the + (Up) button two to change the display to“3.OPR”.
3.
Press the Information Button once to access the Operation Mode menu.
4.
Press the + (Up) button once to set the boiler to operate at 1-stage MIN
(“MIN.1”).
5.
To set the boiler to operate at DHW 2-stage MAX, press the + (Up)
button 4 times or until "D.MX.2" is displayed.
6.
To exit the Operation Mode and return the boiler to normal operation,
press the Reset button twice.
Diagnostics
Mode
Reset
Navien America, Inc.
20 Goodyear lrvine, CA 92618
TEL +949
-420-0420 FAX [phone]
www.navienamerica.com
Digital pressure
manometer