Furrion FWH09A-AM User manual

2.4GPM Tankless Gas Water Heater
User Manual Model: FWH09A-AM
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1
Thank you for purchasing this Furrion® product. Before operating your new product, please read these instructions carefully.
This will ensure safe use and reduce the risk of injury. This instruction manual contains information for installation, operation,
maintenance of the product and safe use.
Please keep this instruction manual in a safe place for future reference. Be sure to pass on this manual to any new owners of
this product.
The manufacturer does not accept responsibility for any damages due to not observing these instructions.
WARNING: If the information in these instructions is not followed exactly, a fire or explosion
may result causing property damage, personal injury or death.
−Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any
other appliance.
−WHAT TO DO IF YOU SMELL GAS
●Evacuate all persons from vehicle.
●Shut off gas supply at gas container or source.
●DO NOT touch any electrical switch, or use any phone or radio in vehicle.
●DO NOT start vehicle’s engine or electric generator.
●Contact nearest gas supplier or qualified service technician for repairs.
●If you cannot reach a gas supplier or qualified service technician, contact the nearest fire
department.
●DO NOT turn on gas supply until gas leak(s) has been repaired.
−Installation and service must be performed by a qualified installer, service agency or the gas
supplier.
Table of Contents
Table of Contents................................................................................................................................................................................... 1
Explanation of Symbols ........................................................................................................................................................................ 2
Important Safety Instructions.............................................................................................................................................................. 2
Ensuring a Safe Operating Environment ...................................................................................................................................................................................2
Responsibilities of the Operator....................................................................................................................................................................................................2
About Your Product ............................................................................................................................................................................... 3
Product Overview ................................................................................................................................................................................................................................3
Product Features..................................................................................................................................................................................................................................3
Basic Function .......................................................................................................................................................................................................................................3
Installation .............................................................................................................................................................................................. 3
General Installation Safety...............................................................................................................................................................................................................3
What’s in the Box ..................................................................................................................................................................................................................................4
Tools Required (Not Provided).......................................................................................................................................................................................................4
Prepare Cutout Opening...................................................................................................................................................................................................................5
Prepare Utilities.....................................................................................................................................................................................................................................6
Prepare Wall Control...........................................................................................................................................................................................................................7
Prepare Water Heater.........................................................................................................................................................................................................................8
Prepare Water Heater Door.............................................................................................................................................................................................................8
Water Heater Installation .................................................................................................................................................................................................................8
Leak Check ............................................................................................................................................................................................................................................10
Functional Test ......................................................................................................................................................................................................................................11
Operation................................................................................................................................................................................................. 11
Controller Operation...........................................................................................................................................................................................................................11
Safe Operation ......................................................................................................................................................................................................................................11
Water Control Valve.............................................................................................................................................................................................................................12
High Altitude Use .................................................................................................................................................................................................................................12
Cleaning and Maintenance ................................................................................................................................................................... 12
Storage and Transit.............................................................................................................................................................................................................................12
Winterizing Water Heater..................................................................................................................................................................................................................12
Routine Inspection...............................................................................................................................................................................................................................13
Filter Cleaning........................................................................................................................................................................................................................................14
Pressure Safety Valve Maintenance............................................................................................................................................................................................14
Hard Water and Decalcification.....................................................................................................................................................................................................14
Error Code............................................................................................................................................................................................... 15
Troubleshooting ..................................................................................................................................................................................... 16
Wiring Diagram ....................................................................................................................................................................................... 17
Specifications......................................................................................................................................................................................... 17

2
Explanation of Symbols
This manual has safety information and instructions to help
you eliminate or reduce the risk of accidents and injuries.
Always respect all safety warnings identified with these
symbols. A signal word will identify safety messages and
property damage messages, and will indicate the degree or
level of hazard seriousness.
DANGER
Indicates an imminently hazardous situation which, if not
avoided, will result in death or serious injury.
WARNING
Indicates a potentially hazardous situation which, if not
avoided, could result in death or serious injury.
CAUTION
Indicates a potentially hazardous situation which, if not
avoided, may result in minor or moderate personal injury, or
property damage.
Important Safety Instructions
Read these instructions carefully to ensure safe and correct
operation of your appliance. Retain the instruction manual
and installation instructions for future use or for subsequent
owners.
Ensuring a Safe Operating
Environment
DANGER
Suffocation or Fire Hazard
●Exhaust gases are hot and contain carbon monoxide,
do not breath or obstruct the exhaust gases.
Failure to follow the instruction will lead to serious injury,
property damage or death.
●NEVER use this appliance in enclosed spaces or tents.
●ALWAYS turn the appliance off, and shut off fuel supply
while parking the RV in an enclosed space, such as a
garage or repair shop.
●NEVER place seating or picnic tables in direct path of the
exhaust outlet.
●DO NOT use this water heater without a working
carbon monoxide detector installed in the RV. Follow
the manufacturer's instruction and guidelines for its
installation.
●ALWAY keep the air inlet and exhaust outlet free of
obstructions in order to ensure clean combustion.
●DO NOT place articles on or against the appliance.
●DO NOT lean any objects against the water heater’s
access door or place any foreign objects within 24" (610
mm) of the access door.
●DO NOT use or store flammable materials near the
appliance.
●DO NOT spray aerosols in the vicinity of the appliance
while it is in operation.
●DO NOT modify the appliance.
Responsibilities of the Operator
●The operator is responsible for their own health and
safety, persons with pacemakers should discuss with their
doctor before opening the access door, or performing any
service repairs.
●The operator is responsible for the water quality used in
the appliance.
●The operator is responsible for all routine inspections
found in the Cleaning and Maintenance section of this
manual.
●The operator is responsible for using and maintaining gas
cylinders as specified by the RV manufacturer.
●The operator is responsible for ensuring no spray water
enters the appliance when cleaning the RV.
●The operator is responsible for using the appliance for
potable water only. They are responsible for ensuring
non-potable water sources, components, or heating
systems, new or old, are not connected in any means to
the appliance.
While Driving
●The operator is responsible for ensuring all components
are seated and locked in place before moving the RV,
check the following:
− Access door is flush with the mounting plate.
− Door locker is engaged. (Fig. 1)
Door Locker
Fig. 1
●The operator is responsible for ensuring the gas system
is turned off at the gas cylinders before transit. Turn off all
necessary valves as indicated by the RV manufacturer.
●The operator is responsible for making sure the appliance
is off when refueling, traveling through tunnels, parking in
garages or car ports, or on ferries.

3
About Your Product
Product Overview
Access Door
Exhaust Vent Door Trim
Door Cover
Door Latch
Wall Controller
POWER
UP
DOWN
o
F /
o
C
ON/OFF
O
F
O
CFLAME
Up Button Down Button Temperature
Unit Switch Button
Power Button
LED Display
Product Features
The appliance is equipped with the following features:
Flame Monitoring
If the flame goes out, the gas supply to the burner is switched
off.
Low-Voltage/Over-Voltage Shutdown
If the voltage drops below 10V DC (or rises above 17V DC),
the appliance shuts off.
Over-current Protection
If there is a short circuit in the appliance (>10 A), a fuse on the
control unit is activated and the appliance is switched off.
Flue Fan Monitoring
If there is a failure of the flue fan, the gas supply to the burner
is switched off.
Hot Water Temperature Monitoring
A water over-temperature switch avoids excessively high
water temperatures in case of an error.
Basic Function
Based on the hot water demand, the tankless water heater
will heat incoming cold water to a desired output temperature
by monitoring key sensors to regulate the thermal energy
released over a large heat exchanger. This creates a more
useful and energy efficient heating system versus the
conventional tank water heater that wastes fuel during re-
heat cycles and is limited on volume output.
Installation
DANGER
Suffocation and/or Fire Hazard
●Observe all installation material in accordance with
governing codes and ordinances.
Failure to the follow instructions will result in serious injury,
property damage, or death.
The installation of this appliance, along with all subsequent
components to support installation and operation of the
appliance, must conform with country, state and local codes.
In the absence of such codes, refer to the latest editions of:
●USA:
− NFPA 1192 - Recreational Vehicles (RV)
− ANSI A119.5 - Park Model RV
− ANSI/RVIA LV - Low Voltage Standard
− NFPA 70 - National Electric Code
●Canada:
− CSA Z240 RV Series - Recreational Vehicles
− CSA Z241 Park Model RV
− CSA C22.1 - Canadian Electric Code
General Installation Safety
WARNING
Electrical Shock and/or Fire Hazard
●Disconnect power before installation.
●Turn off all gas to the supply system.
Failure to do so can result in serious injury or Death.

4
CAUTION
Always wear protective gear such as gloves,
eyewear and clothing to avoid injuries during
installation and servicing of the product.
●For Recreational Vehicle (RV) installation only!
NOTE: This water heater is certified ANSI Z 21.10.3 /
CSA4.3-2019 for installation in Recreational Vehicles (RV)
and is not for use in Marine or Space Heating Applications.
RV’s are recreation vehicles, having their own power or
towed by another vehicle, designed as temporary living
quarters for recreation, camping, or travel use.
●Any Installation must be performed by a qualified person,
in accordance with this instruction manual.
●DO NOT use test pressures higher than 40in-wc (1.45PSI)
to test the gas leaks.
●DO NOT attempt to modify the appliance.
●DO NOT alter the appliance for a positive grounding
battery system.
●DO NOT move the appliance by grabbing the interior
components.
●Make sure all exhaust gases are directed outside the RV.
●Protect all combustible material from the exhaust gases.
●DO NOT draw air for combustion from occupied spaces.
●Always disconnect the 12V appliance (to protect the
control from surges that may occur) when performing
Dielectric (hi-pot) testing, welding, electrical, etc... work on
the coach.
●Only use with a proven 12V power source such as battery
or approved converter.
●DO NOT vent the water heater using a venting system
serving another appliance.
●DO NOT install directly into a shower, or near direct heat.
What’s in the Box
WARNING
Suffocation Hazard
●Dispose packaging material or keep from reach of small
children.
Failure to follow instruction could lead to serious injury or
death.
Remove product from packaging and make sure you have
the following list of items included. If any item is damaged or
missing, contact your Furrion dealer.
Part Description Quantity
Water Heater (For Model: FWH09A)
Main Body 1
Wall Controller 1
Instruction Manual 1
Warranty Manual 1
Door Assembly (Packed Separately)
Door assembly
(Assembly of door
cover and mounting
frame)
1
Installation Guide 1
NOTE: The door assembly for the water heater is packed in
another box, please contact your dealer if any of parts are
damaged or missing.
Tools Required (Not Provided)
Part Description
Electric Drill
Bit size: ⁄" (3mm) and ¾" (19mm)
Eye Protection
Gloves
Wire Stripper Pliers
Adjustable Wrench x 2
Tape Measure
Pencil
Phillips Screwdriver
Flat Blade
Cutting Knife
Sealant Gun

5
Prepare Cutout Opening
1. Choose a location to place the appliance, based on the
following criteria:
− DO NOT install in the front facing portion of the RV
to minimize damaging contamination from road grim,
debris and wet roads when traveling.
Important: It is not advised, but if installed on the rear
of the RV, the owner of this appliance must increase
routine inspections, from this manual, after each time
travelled.
− Do not install the appliance in an outdoor enclosed
area.
− DO NOT install the appliance in any location where the
exhaust vent may be covered or obstructed when a
swing door, bag door, slide out, pop up, etc. is partially
or fully extended.
− DO NOT install this appliance on any door or slide out
area.
− Do not install the appliance where the access door is
less than
- 9" (229mm) from any opening into the vehicle
- 36" (914) from any motor driven air intake
- 36" (914mm) from the any gas tank connection or
ventilation.
NOTE: These are guidelines, refer to NFP1192, Z240
RV edition for specific requirements.
− Choose a convenient location where supply water, LP
gas, and 12V DC is accessible to the back side of the
appliance for installation and servicing.
− The water heater is designed to be installed on a flat
floor (made of Wood or Linoleum) or a fixed platform.
− It is recommended that the appliance be located in a
central location to the hot water loads.
− Choose a location where clearances to combustible
surfaces and the appliance are:
- 1" to top surface.
- 0" to all other surfaces.
NOTE: To install on a carpeted area, a metal or wood panel that
extends at least 3 inches beyond the width and depth of the water
heater is required to install under the unit.
2. Create a cutout with the following dimensions A and B of
Fig. 2.
NOTE: The opening for the water heater should be right
angle corners.
C
A
B
Fig. 2
RV Flooring
RV Out-wall
Dimension
A B C
12⅝”~ 12¾”
(321~325mm)
12¾”~ 12⁄”
(324~326mm)
Min. 23½”
(Min. 597mm)
3. Make sure that the front edge of the opening is
surrounded by a solid frame to firmly anchor the water
heater. If needed, construct the opening by using
1.5" x 1.5" min. wood or aluminum framing.
NOTE:
− Fiberglass, filon, and corrugated aluminum (Mesa 1")
are all acceptable exterior wall siding solutions.
− The exterior wall opening must be the same dimensions
with no radius corners.
4. Refer to depth "C" for minimum rear clearances, for such
items as cabinets, appliances and utility entry locations.
5. Refer to Fig. 3 for adequate spacing from other items on
the RV wall to the door assembly.
B
A
Fig. 3
Cutout
Spacing
Door Assembly A B
FWH09EA-PS/BL Min. 1¾” (45mm) Min. 1 ⅞” (47mm)
FWH41EA-PS/BL Min. 2¾” (70mm) Min. 1 ⅞” (47mm)
FWH46EA-PS/BL Min. 2¾” (70mm) Min. 2⁄” (72mm)
6. Make sure the appliance is supported by a solid floor or
platform with adequate weight-bearing capacity. (Fig. 4)
RV Flooring
Fig. 4
7. If necessary, create a platform to support the water heater.
Fig. 5 and Fig. 6 are some common solutions. Ensure
the platform is level front to back, and side to side after
securing to the RV.
6"~8”
(152~203mm)
B
Flooring
C
A
7”~11½"
(178~292mm)
Wooden Mat
Flush Platform
Fig. 5

6
6"~8”
(152~203mm)
B
Flooring
C
A
7”~11½"
(178~292mm)
Fig. 6
Flooring
Wooden Mat
Flush Platform
Existing Cutout
1. Determine your existing cut-out and choose the
appropriate door assembly. (Fig. 7)
A
B
Fig. 7
RV Flooring
RV Out-wall
Door Assembly and Description Existing Cutout Dimension
A B
FWH09EA-PS/BL
Door 16⅛” x 16⅛” (410x410mm)
12⅝” ~ 15”
321 ~ 381mm
12⁄” ~ 15”
322 ~ 381mm
FWH41EA-PS/BL
Door 16⅛” x 18⅛” (410x460mm)
12⅝” ~ 15”
321 ~ 381mm
12⁄” ~ 17”
322 ~ 432mm
FWH46EA-PS/BL
Door 18⅛” x 18⅛” (460x460mm)
12⅝” ~ 17”
321 ~ 432mm
12⁄”~ 17”
322 ~ 432mm
2. The opening may need to be adjusted to accomodate
installation requirements of Fig 2. Refer to the door
assembly packaging for additional installation
instructions, requirements and options for resizing the
opening. (Fig. 8)
FWH09EA-PS/BL FWH41EA-PS/BL FWH46EA-PS/BL
Fig. 8
Prepare Utilities
Refer to Fig 9, 10, 11 for a general connection diagram.
Gas Connection (Fig. 9)
Gas Inlet
Gas Supply
Gas Inlet
Fig. 9
Electrical wiring (Fig. 10)
Fig. 10
12V DC
Power
Supply
Wall
Controller
12V
15A
Blue
White -
12V DC
Ripple<1Vpp
Blue
Switch ON-OFF (Optional)
Wiring
Water plumbing (Fig. 11)
A
B
Fig. 11
Shower Tap 2 Tap 1
NOTE:
Valve A, B
Bypass Position
HOT Water Outlet
COLD Water Inlet
NOTE:
●The drawings are not intended to describe a complete
system. It is the installers responsibility to determine the
necessary components for a working system.
●The drawings do not imply compliance with state or
local code requirements or regulations. It is the installers
responsibility to make sure that the installation is in full
compliance with all state or local code requirements or
regulations.
●Optional: The bypass valve can be installed (Fig 11) to
facilitate winterizing the coach. It is not required as anti-
freeze can be used in the appliance, however additional
anti-freeze (about 1L) is required to fill the volume. Refer
to the winterizing section of this manual for instruction
methods.
Gas Plumbing
DANGER
Fire or Explosion Hazard
●Follow all applicable codes, regulations and instruction
material when performing service work
Failure to follow instruction will result in product damage,
serious injury or death.
●Fuel entering the appliance must be in gas phase, liquid
phase must not be used and will result in damage to the
product.
●This appliance is rated for 60,000 BTU/HR, 11~14in-wc.
(27.4~34.9mbar). Follow NFPA1192 and Z240 RV series
for proper pipe sizing based on additional gas burning
appliance loads.
●Use with LP gas (propane) only. Butane or any mixtures
containing more than 10% butane must not be used.
●The gas line must terminate with a ⅜" flared female
compression fitting to connect with the rear gas
connector of the appliance.

7
●A non Metallic Flexible gas hose must be rated for 149oF
(65oC). Anchor appropriately to prevent fatigue and failure
from wear edges.
●Make sure that the operating pressure of the gas supply
corresponds to the operating pressure of the appliance
11~14in-wc (27.4~34.9mbar).
1. Locate entry point for the plumbing to service the
rear of the appliance. Ensure entry point is not in the
footprint space of the appliance. (Fig. 2)
2. Feed gas line into proximity, leave enough length to
flex into position so that when connected no kinks are
created.
NOTE: An approved semi-flexible metallic pipe is
acceptable to connect as an extension from the gas
line to the appliance.
3. Terminate gas line with fittings to connect to the
appliance.
Electrical Wiring
WARNING
Electrical Shock Hazard
●Disconnect all power before performing any work.
●Always use a certified and proven 12V isolated power
supply, that is properly grounded to the RV.
●Follow all applicable codes, regulations and instruction
material when performing service work.
Failure to follow instruction could result in serious injury or
death.
●Wiring connected to or in proximity of the appliance must
be rated for 140°F (60°C) minimum.
●Use only insulated terminals for all electrical connections.
●The appliance requires a power source that can
adequately provide 10~17V DC to function properly.
Contact furrion for available Power centers, converters
and distribution panels.
1. Select a distribution branch greater than 3A, preferably
15 amp, to provide nominal 12V to the appliance from the
distribution panel.
NOTE: The appliance has a built in 10A fuse, serviceable
from the front of the product. The appliance can be on
a dedicated or shared branch circuit with the same or
higher rating.
Optional: A power switch can be placed in the living
quarters for convenience, but not required as a switch is
located externally on the appliance. If the switch is fused,
make sure it is rated for at least 3amps. See Fig. 10 for
reference.
2. Locate entry point for the wiring to service the rear of
the appliance. Ensure entry point is not in the footprint
space of the appliance (Fig. 2) Make sure any edges are
protected to prevent wire abrasion from occurring.
3. Determine the appropriate wire gauge (AWG) for the 12V
power supply length. Ensure enough wire is available to
make adequate connection.
− 16AWG max. 40 feet (12m)
− 14AWG max. 66 feet (20m)
4. Feed wire from power source to the entry point. Make
connection to the power source.
Water Plumbing
●The plumbing must be rated to supply between 35-70PSI
nominal.
●Connections can be made using PEX swivel nut adapters
with NPT straight threads and a cone seal or with a
standard ½” FPT fittings.
●For proper operation this water heater requires a minimum
water flow of 0.32 Gallon per Minute (gpm).
1. Locate entry point for the plumbing to service the
rear of the appliance. Ensure entry point is not in the
footprint space of the appliance. (Fig. 2)
2. Create a piping layout to supply the appliance and all
faucets, reference Fig. 11.
NOTE:Dry fit tubing and fittings before clamping
together. Adjust sections to avoid excessive stress on
the fittings when assembled to the appliance. It may be
helpful to fit the appliance into position to determine the
appropriate piping layout.
3. Clamp and seal all fittings together. Terminate piping
with the appropriate fittings.
Prepare Wall Control
1. Determine a location to install the wall controller inside the
RV.
2. Drill a ¾" hole and clean edges.
3. If necessary, run two electrical wires that extend the
wall control connections (blue wires) to the appliance
connections (blue wires) using the appropriate wire size.
(Fig. 12)
− 16AWG max. 65ft (20m).
¾”
Fig. 12

8
Prepare Water Heater
1. Take the water heater out of its packaging by grasping
the metal sides of the housing and lifting upward until fully
removed from the box.
2. Remove protective caps for COLD (blue), HOT (red) water
connector and GAS connector from back side. (Fig. 13)
Fig. 13
Cover Cap (Red)
Cover Cap (Blue)
HOT
Cover Cap (Black)
COLD
GAS
3. A pply adequate water sealing material, e.g. butyl tape
(recommended width: 1”, not provided), around the entire
backside flange area and holes. (Fig. 14)
NOTE: Do not use adhesive sealing material e.g. silicone
for the watertight seal.
Fig. 14
Continuous bead
around corners
Butyl Tape
Prepare Water Heater Door
WARNING
Suffocation and/or Fire Hazard
●Use only the door kit assembly specified for this
product, other types may restrict combustion air and
exhaust gases
Failure to follow instruction could lead to serious injury,
property damage or death.
●The door of the Furrion water heater is fixed to the
mounting flange by a latch.
●Remove the access door and frame from the box,
separate the components. (Fig. 15)
− Step
1
: separate the access door from the mounting
frame. Lift the latch and rotate 90° to unlock the door
cover from the trim.
− Step 2: Pull the access door from the mounting frame.
NOTE: The baffle does not need to be removed.
1
2
Slot
Door Latch
Access Door
Door Cover
Baffle
Fig. 15
Water Heater Installation
1. Position the water heater carefully into the frame opening ,
evenly space the flange to the exterior wall of the RV. (Fig. 16)
NOTE: Ensure area beneath and behind the appliance is
clean without debris and obstruction. Carefully slide the
appliance across the floor to prevent linoleum damage.
Fig. 16
Gas Connection
1. Connect the gas service line to the ⅜” LP gas flared fitting
on the back of the appliance. Use two wrenches to tighten
the compression fitting. Avoid dama ging the unit by over-
tightening. (Fig. 17)
NOTE: Do not use sealing tape or compound on the
compression type fitting.
GAS
Fig. 17
Electrical Connection
1. Set the power switch (Fig. 18) in front of the water heater
to the “OFF” position.
Power
Switch
Fig. 18

9
2. Connect the power supply wires (on rear of water heater
- white and black wire) to the appropriate nominal 12V DC
power source connection. (Fig. 19)
NOTE: The black wire is positive (+) and the white wire is
negative (-).
3. Connect the wall controller wires (2 blue wires on the
appliance). (Fig. 19)
NOTE: Polarity does not matter, the wires can be
connected to either blue wires.
12V DC
Power
Supply
Wall
Controller
12V
White: -12V
Not Provided
Black: +12V
Blue
Fig. 19
Water Connection
1. Connect both HOT and COLD water lines to the appropriate
½”NPT fittings. (Fig. 20)
NOTE:
− DO NOT over tighten connection fittings.
− For new installations, it is advisable to flush the water
system of debris before connecting to the appliance.
Fig. 20
COLD
HOT
Securing the Water Heater
1. Insert the door flange into the water heater housing and
press the flange firmly against the sidewall. (Fig. 21)
Fig. 21
2. Secure the flange to the vehicle using 12 - #8 (min 1") pan
head screws (not provided) through each hole along the
perimeter. Verify that a tight seal exists between the side
wall and the flange. (Fig. 22)
NOTE: Ensure the butyl tape completes a tight seal
between the RV siding and appliance flange. If gaps exist,
remove the appliance and apply a double layer of butyl
tape.
Fig. 22
3. Apply a liberal amount of sealant around the door frame
to fill any gaps to the RV wall. (Fig. 23) Wipe any excess
sealant.
Fig. 23
4. Insert the door into the pins at the bottom of the water
heater. (Fig. 24)
Hole Pin
Fig. 24
5. Align the latch on the flange with the slot on the door, then
push the door and rotate the latch to lock the door into
place. (Fig. 25)
− Step
1
: Pull and rotate the lever 90° to lock the latch.
− Step 2: Turn down the folding latch to lock.
NOTE: Damage to the assembly door and the RV if the
assembly door is not closed properly! Make sure that
the assembly door is flush with the cover plate when
closed.
Fig. 25
Door Latch
Slot