Navien NFB-301C User manual

1
󱂓Unpacking
Navien
Condensing
Boiler
User’s
Information
Manual,
Installation
& Operation
Manual
Air Vent Condensate
Trap
Vent
Termination
Caps
Wall Flanges
Wall Mounting
Bracket (with
Anti-Vibration
Rubber Pad)
* Included in
the L box
Tapping
Screws and
Anchors
(x6)
Pressure
Relief Valve,
Heating
Conversion
Kit
Outdoor
Temperature
Sensor and
Cable
Air Vent
Bushing
(11/2
in to 3/4 in)
Universal
Temperature
Sensor
(with Clip)
PRV-Air Vent
Adapter
(with Clip)
Caps (x2)
Double
Nipple
(3/4
in to 3/4in)
Model
NFB-301C/399C
Quick Installation Guide
STEP 1 Before Installing
Read the Installation & Operation Manual before installing.
This product must be installed and serviced by a licensed plumber,
a licensed gas tter, or a professional service technician. Navien is
not liable for any damages or defects resulting from improper
installation.
WARNING
Follow all local codes and/or the most recent edition of the National Fuel Gas Code (ANSI
Z223.1/NFPA 54) in the USA, or the Natural Gas and Propane Installation Code in Canada
(CAN/CGA B149.1).
Safety
DO NOT install the boiler in areas with excessively high humidity.
Location Requirements
Select the best location on “Choosing an Installation Location”in the Installation &
Operation Manual.
Allowable minimum clearances
Top
Back
Side
Side
Front
Bottom
Clearance from: Indoor Installation
Top 12 in (305 mm) minimum
Back 0.5 in (13 mm) minimum
Front 24 in (610 mm) minimum
Sides 6 in (152 mm) minimum
Bottom 24 in (610 mm) minimum
STEP 2 Installing
󱂔Checking the Rating Plate
>
This appliance is certied for use at altitudes up to 4,500 ft (1,370 m) In accordance to the latest CAN/CGA 2.17-High Altitude
Installation procedures at normal manifold pressure.This appliance has also been tested up to 10,100 ft(3,078 m).
For installations at altitudes up to 10,100 ft(3,078 m), follow the directions provided in the High Altitude Installations sections
of the lnstallatlon Manual. *Cet appareil est certié pour une utilisation à des altitudes de 0 à 4,500 pieds (1,370 m) conformément aux
toutes les procédures d'installation à haute altitude CAN/CGA 2.17 à une pression normale. Cet appareil a été testé jusqu'à 10,100 pieds
(3.078 m). Pour les instructions d'installation à une altitude supérieure à 10.100 pieds, suivez les instructions fournies dans la section des
installations à haute altitude du manuel d'installation.
7
2017
This boiler is congured
for Natural Gas from the
factory. If conversion to
Propane Gas in required,
the conversion kit supplied
with the boiler must be
used.
WARNING
·Before connecting the gas supply, determine the gas type and pressure for the boiler by
referring to the rating plate. Use only the same gas type indicated on the rating plate. Using a
dierent gas type will result in abnormal combustion and malfunction of the boiler. Gas
supplies should be connected by a licensed professional only.
·The appliance and its gas connection must be leak tested before placing the appliance in
operation.
·This boiler cannot be converted from natural gas to propane or vice versa without a Navien gas
conversion kit. Do not attempt a eld conversion of this boiler without a Navien gas conversion
kit. Doing so will result in dangerous operating conditions and will void the warranty.
Navien Inc. is not liable for any property damage and/or personal injury resulting from
improper conversions.
󱂕Mounting on the Wall
>
CAUTION
Do not install the boiler on drywall
without proper reinforcement.
1Remove the wall bracket from the L box.
Mount the wall bracket and the boiler following the instructions below for your installation type.
Note
The anti-vibration rubber pad must be mounted with its arrow mark ( ) facing outward.
Mounting to a wood studded wall:
Mount the wall bracket using the lag bolts provided.
Mounting to a concrete wall:
Mount the wall bracket using the anchor bolts provided. To mount the anchor bolts, drill a 3/8"
diameter hole 3-1/2" deep and insert anchor.
Mounting to a metal studded wall:
Mount the wall bracket using eld supplied toggle bolts capable of supporting 100 pounds each.
2
󱂖Removing the Front Cover
>
Unfasten the 4 latches
(2 at the top and 2 at the bottom)
to remove the front cover.

2
󱂗Gas Piping Connections
>
Gas Supply Line
Gas Inlet Adapter
Gas
Regulator
Gas supply
Bottom View
The boiler is
recommended to be
the rst appliance to
be connected to the
gas supply line.
The gas meter capacity
must be greater than
the total gas capacity of
connected appliances.
Example:
Gas meter
425 CFH ≥Boiler 195 CFH +Furnace 58.8 CFH +Domestic gas stove 63.7CFH
* 1 CFH=1,020 Btuh
3/4" rigid pipe can be used; refer to the sizing tables in the Installation & Operation
Manual for limitations. Avoid using 3/4" corrugated connectors or tubing as noise may
occur.
󱂙Condensate Drain Connection
>
A condensate drain pipe must be connected to the ¾”condensate outlet tting at the
bottom of the unit and water must be poured into the exhaust connection to ll the
condensate trap.
Condensate trap
Floor drain
Water
The end of the ¾” (NPT) plastic piping should drain into a laundry tub or into a oor
drain.
Note Do not submerge the end of
the pipe in water.
a
b
c
d
Direct to the external drain To the drain
via a
neutralizer
External drain
To the laundry tub
To the laundry tub
via a condensate pump
󱂘Water Piping Connections
>
Water Piping Connections
Heating
Supply
Condensate
Outlet
Heating
Return Gas
Connection
From
System
Expansion Tank
Backow Preventer
Pressure Reducing
Valve
Make-up Water
Pump
To System
Air Separator
Pressure Relief Valve
Space Heating System
A pressure relief valve must be installed when installing piping for a heating system.
Install the included 3/4in, maximum 50 psi pressure relief valve on the space heating supply.
An ASME approved HV pressure relief valve for space heating system is supplied with the boiler.
You may install the pressure relief valve on the space heating supply of the Navien Manifold System, or on the top connection along
with the air vent (and an external LWCO, if required).
CAUTION
Do not solder piping directly onto the water connections, as the heat may cause damage to internal components. Use
threaded water connections only.
System Fill Connection
1
2
3
Pressure Relief Valve
Air Vent
PRV-Air Vent
Adapter
Air Vent
Bushing
Air Vent
Bushing
PRV-Air Vent
Connection
Clip
Air Vent
External
LWCO
Pressure
Relief Valve
The Navien NFB boiler comes with an air vent and an
adapter bushing that must be connected to the air vent
connection. The vent eciently removes the air from
the space heating system.
To secure the adapter to the tting, install the provided
clip after inserting the PRV-air vent adapter into the
connection on top of the unit.
When installing the air vent, install the air vent bushing
between the air vent and the top connection.
Before lling the boiler, remove the air vent cap to allow
the system to ll properly. Replace the cap when the
system is full.
Note Prior to connecting piping to the boiler, ush
the entire system to ensure it is free of
sediment, ux, scale, debris or other
impurities that may be harmful to the system
and boiler. During the assembly of the
heating system, it is important to keep the
inside of the piping free of any debris
including construction dust, copper burr,
sand and dirt.
Note Ensure that the vent cap is re-installed and
the vent screws on the system and boiler
pumps are properly tightened before testing
or operating the system.

3
󱂚Venting
>
󱂛Electrical Connections
>
Vent Termination Options
Horizontal vent termination
Interior view
Intake Air
Exhaust Gas
12" (300 mm) min.
12" (300 mm) min.
Exterior view
Vertical vent termination Sidewall vent termination
12" min. from any
obstruction above,
below, left, or right
12" (300 mm) min.
12" (300 mm) min.
36" (900 mm) min.
12" (300mm) min.*
Concentric Vent Termination
Sidewall installation
Combustion Air
Combustion Air
1" (25mm) min
Maintain 12" min.
clearance above
highest anticipated
snow level or grade.
Vent
Roof installation
Vent
Vent
Combustion Air
Maintain 12" min.
(18" min. for Canada)
clearance above
highest anticipated
snow level maximum
of 24" above roof.
Combustion
Air
Venting Length
4” pipe venting 3” pipe venting
8
1
3
7
2
Maximum Length 150'
Maximum number
of elbows: 8
3-to-4 inch
6
1
3
4
5
2
Maximum number
of elbows: 6
Maximum Length 60'
·90˚ elbow = 5 linear feet of venting
·45˚ elbow = 3 linear feet of venting
·90˚ elbow = 5 linear feet of venting
·45˚ elbow = 3 linear feet of venting
Exhaust Vent Piping Materials
·All Navien boilers are Category IV appliances.
·The venting system should be approved for use with Category IV appliances (typically Type BH
Special Gas Vent approved by UL 1738-S636).
·Venting requirements in the USA and Canada are dierent (see below).
Navien recommended venting materials
Locale Recommended Vent Materials
USA
·PVC/CPVC Schedule 40 or 80 (Solid Core)
·Approved Polypropylene (PP)**
·Approved Stainless Steel (SS)***
Canada*
·Type BH Special Gas Vent Class IIA (PVC)
·Type BH Special Gas Vent Class IIB (CPVC)
·Type BH Special Gas Vent Class IIC (Polypropylene/Stainless Steel)
* For installation in Canada, eld-supplied plastic vent piping must comply with CAN/CGA B149.1 (latest
edition) and be certied to the Standard. For Type BH Gas Venting Systems, ULC-S636. Components of this
listed system must not be interchanged with other vent systems or unlisted pipes or ttings. All plastic
components and specied primers and glues of the certied vent system must be from a single system
manufacturer and must not be intermixed with another system manufacturer’s parts.
The supplied vent connector and vent termination are certied as part of the boiler.
** Approved Polypropylene Systems include:
Duravent PolyPro® SW (Rigid): 3PPS-xxx (3”) or 4PPS-xxx(4”)
Duravent PolyPro® (Flexible): 3PPS-FLEXxx (3”), 3PPS-FAM (3” Rigid-to-Flex Male Adapter)
Centrotherm Innoue® SW (Rigid): ISxx03xx (3”) or ISxx04xx (4”)
Hart & Cooley Polyue™ SW (Rigid): 3PF-xx (3”) or 4PF-xx (4”)
Z-Flex Z-DENS SW (Rigid): 2ZDP_(3” or 4")
*** Approved Stainless Steel Systems include:
Duravent FasNSeal® (Rigid): FSA-PVC3 or FSA-PVC4 (3”or 4”PVC to FasN Seal Appliance Adapter),
FSxxxxx03 or FSxxxxx04 (3” or 4”)
Heat Fab Saf-T Vent® EZ Seal: 9301PVC or 9401PVC (3” or 4”PVC/CPVC Outlet Boiler Adapter),
93xx or 94xx (3” or 4”)
External LWCO Connection
(if required by local codes)
Power Connection
NULTI SW
T/S DHW
3.LWCO
2.AC24VL
1.AC24VN
FLOW SW LP SW
OUT DOOR DHW TANK
(+)
(-)
SYSTEM
SUPPLY
SYSTEM
RETURN
W
CRWCR W C
RWC
LWCO
LINE
LINE
Neutral
Refer to your local codes to determine if an
LWCO device is required for your system and
ensure that the built-in device meets the
requirements.
120 V AC 60 Hz
Min. 2 Amp current with proper
grounding
CAUTION
Using abnormally high or low AC
voltage may cause abnormal operation,
thereby causing re which reduces the
life expectancy of this product.
CAUTION
Disconnect the power to
the boiler before installing
any wire connections on
the main PCB.
Safety
DO NOT touch
the power
cord with wet
hands.
DO NOT allow
the boiler to be
exposed to
excessive
amounts of
water.
Conrmation of DIP Switch Settings
DIP Switch 1 (6 switch unit) DIP Switch 2 (8 switch unit)
SW Function Setting
1 & 2 Operation
Status
Normal Operation 1-OFF,
2-OFF
2Step MAX 1-ON,
2-OFF
1Step MIN 1-OFF,
2-ON
1Step MAX 1-ON,
2-ON
SW Function Setting
1Gas Type Natural Gas
Propane Gas
1-OFF
1-ON
2 & 3 High
Altitude
0-1,999 ft
(0-609 m)
2-OFF,
3-OFF
2,000-5,399 ft
(610-1,645 m)
2-ON,
3-OFF
5,400-7,699 ft
(1,646-2,346 m)
2-OFF,
3-ON
7,700-10,100 ft
(2,347-3,078 m)
2-ON,
3-ON
4 Reserved - -
5 & 6 Country US/Canada 5-OFF,
6-OFF
7
Space
Heating
Thermostat
Used 7-OFF
Unused 7-ON
8
Exhaust
Temperature
Control
Used 8-OFF
Unused 8-ON
Note When PCB DIP switch 2 #8 is set to
On, ensure that CPVC, polypropylene,
or stainless steel is used for exhaust
venting.

4
STEP 3 After Installing
󱂓Opening All the Valves
>
Gas Valve Space Heating System Valves
Closed Open
Shut-o
valves
Power ON Turn On or O Adjust Temperatures View Basic Information Resetting the Boiler
Space Heating DHW Space Heating
Temperature
DHW Temperature
To turn the boiler on:
1. Connect the power cord. When the
power is on, the User Settings
screen is displayed.
2. Select the language you want to use
and set the vent type, current date,
and time by tapping your selections
on the screen.
3. Tap Done on the top right of the
screen to complete the settings.
To turn the Space
Heating on or o,
tap SH ON on the top
left of the screen.
To turn the DHW on or
o, tap DHW ON on the
top right of the screen.
To adjust the heating
temperature on the
screen, tap ( ) or ( )
to select the space
heating temperature in
the SH Set Temp menu.
The current temperature
setting is displayed in
the menu.
To adjust the heating
temperature on the
screen, tap ( ) or ( )
select the DHW Indirect
Supply temperature in
the DHW Set Temp
menu. The current
temperature setting is
displayed in the menu.
1. To view information
about the boiler, tap
the Control button
() > Status on the
screen.
2. Tap an item to view
the information.
Note If resetting does not solve the problem,
refer to the troubleshooting section of
the User’s Information Manual or contact
the service center.
If an error message
appears during boiler
operation, reset the
boiler to resolve the
problem. Press and hold
the Reset button on the
front panel to reset the
boiler.
1
Open Closed
2
Open a hot water
faucet. The boiler
should turn on and
the gas in the gas
supply line will be
purged.
34<NFB-301C> <NFB-399C>
Shut o the manual gas valve. Leave the faucet on until the boiler shuts down
due to a lack of gas supply, and then turn o the
hot water faucet.
Unfasten the 4 latches (2 at the
top and 2 at the bottom) to
remove the front cover.
Loosen the screw indicated in the gure and connect a
manometer to the pressure port. Reset the manometer to zero
before use.
5
Open
Re-open the manual
gas valve and check
for leaks.
Open multiple
xtures that have
high ow rates, such
as bathtub and
shower faucets, to
ramp the boiler up to
its maximum ring
rate.
6
NG: 3.5”–10.5”WC
LP: 8.0”–13.5”WC
Recommended
Gas Pressure Settings:
<NFB-301C> <NFB-399C>
Check the inlet gas pressure reading on the manometer.
If not,
Gas supply
Adjust the inlet gas pressure with gas
regulator.
CAUTION
The boiler cannot function properly without sucient inlet gas pressure. Measuring the inlet gas pressure should be performed by a licensed professional only.
Navien, Inc.
20 Goodyear, Irvine, CA 92618
Tel: [phone], Fax: [phone]
www.navien.com
󱂖Installing the Front Cover
>
󱂗Ensure Maximum Water Flow
>
After running the boiler for the rst 10 minutes, turn it o and clean the cold water lter
and the space heating return strainer to remove any trapped debris.
󱂘Final Check
>
A trial run should be performed in accordance with the Installation checklist listed in
the boiler’s Installation & Operation Manual.
󱂔Operating the Boiler
>
󱂕Measuring the Inlet Gas Pressure
>