Gas Conversion - Navien NCB-180 Service Manual

4.3 Gas Conversion

NCB Series boilers are configured for use withNatural 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" or 4mm Allen Wrench
 Combustion Analyzer or Dual Port Manometer
 Gas Leak Detector
Included Items:
 Gas Orifice (refer to table below)
NG
Boiler
1STAGE
NCB-180 Ø4.80
NCB-210 Ø6.10
NCB-240 Ø6.10
Table 1. Orifice size
Gas Pressure and Conversion Kit Number Labels
26 NCB Service Manual
NP
2STAGE 1STAGE 2STAGE
Ø5.95 Ø3.80 Ø4.70
Ø6.30 Ø4.50 Ø4.80
Ø6.30 Ø4.50 Ø4.80
Procedure:
1. Turn off both gas and water supply to the boiler.
2. Using a Phillips hand 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.
Figure 1. NCB Series Front cover
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 3
Version 1.0