This water heater design has been certified by the Canadian
Standards Association for installation in recreation vehicles. This water
heater is not for use in marine applications.
Atwood G6A-8E in stock and ready to ship
Service Calls & Questions
Location and phone numbers of qualified Service Centers can
be found at our website http://www.atwoodmobile.com
or call 574-264-2131 to have a Service Center List mailed.
Safety Alert Symbols
Safety Symbols alerting you to potential personal safety
hazards. Obey all safety messages following these symbols.
Avoid possible injury Avoid possible injury
Or death And/or
Installation and service must be performed by a qualified
Service technician, Service center, OEM, or Gas Supplier.
FIRE OR EXPLOSION
If the information in this manual is not followed exactly, a
fire or explosion may result causing property damage, personal injury or loss
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
DO NOT turn on gas supply until gas leak(s) has been
Install in recreation vehicles only. RV’s are recreation
vehicles designed as temporary living quarters for recreation, camping, or
travel use having their own power or towed by another vehicle.
All combustion air must be supplied from outside the RV, and
all products of combustion must be vented to outside the RV.
DO NOT vent water heater to an outside enclosed porch area.
Protect building materials from flue gas exhaust.
Install water heater on an exterior wall, with access door
opening to outdoors.
DO NOT modify water heater in any way.
DO NOT HI_POT water hearer unless electronic ignition system
(circuit board) has been disconnected.
DO NOT use battery charger to supply power to water heater
even when testing.
USA And Canada – Follow All
State and Local Codes – In the Absence of Local Codes or Regulation, Refer to
Current Standards of:
Recreation Vehicles ANSI A119.2/NFPA 501C.
National Fuel Gas Code ANSI Z223.1 and/or CAN/CGA B149
Federal Mobile Home Construction & Safety Standard,
Title 24 CFR, part 3280, or when this Standard is not applicable, the Standard
for Manufactured Home Installations (Manufactured Home Sites, Communities, and
Set-Ups), ANSI A255.1 and/or CAN/CSA-Z240 MH Series, Mobile Homes.
National Electric Code ANSI/NFPA No. 70 and/or CSA C22.1
Park Trailers A119.5
CSA standard Z240 RV Series, Recreational Vehicle.
Below is the most common type of installation for the water
heater. However, there are other approved methods such as baggage compartment
(refer to MPD 90093) and flush mounting installations (refer to MPD 93948).
Consult your Field Auditor, Account Manager, or the Atwood Service Department
if you have additional questions.
water heater on floor of coach before erecting side walls. The water tank
must be permanently supported at the same level as the bottom of the
sidewall cutout (by the floor or a raised floor).
install water heater on carpeting, you must install appliance on a metal
or wood panel that extends at least three inches beyond the full width and
depth or appliance.
water heater is installed where leakage of connections or tank will damage
adjacent area, install a drain pan which can be drained to our side of
coach, under water heater.
both ½” NPT water lines – hot water outlet female (FIG 1-A) and cold water
female inlet (FIG 1-B) and 3/8” flared LP gas lines (Fig 1-C).
flexibility in water and gas lines so you can pull unit forward through
wall one inch past skin (FIG 2.
gas line entrance opening by sliding grommet (FIG 1-D) onto 3/8” tubing
(FIG 1-F) before flaring tube (FIG 1-F). Pull gas line and grommet
through opening in housing (FIG 1-C). Connect flare fitting (FIG 1-E) and
press grommet into opening. If gas line tubing is already flared, cut
grommet on once side. Place split grommet over gas line and press it into
use pipe lubricant on threads when connecting hot and cold water
couplings. A suitable plastic fitting is recommended.
5. Erect side walls and cut opening. See chart and FIG 2-A
& B. Frame with 2x2 lumber (or equivalent).
CUTOUT Cut out Dimension Depth
Capacity A B C
10 15-3/4” 16-1/4” 20-5/8”
MINIMUM CLEARANCE FROM COMBUSTIBLE CONTRUCTION
Sides: 0” Top:
Back: 0” Bottom: 0”
all flanges 90 degrees along scored lines (FIG 3).
prevent water leaks caulk thoroughly around opening, including bend slots
(FIG 3-A). Butyl Tape (1”x1/8”) may be substituted for caulking material.
unit against caulking, secure 4-corner brackets FIG 4-A to coach with No.
8 – ¾” round head screws (not furnished) or equivalent. Complete the
installation by inserting the same type of #8 screws in the holes provided
around the flange of the water heater housing. Check all gaskets, they must adhere to the pan creating an air
access door (FIG 5).
hinge pin (FIG 5-A) into clip (FIG 5-B).
cover (FIG 5-C) onto hinge pin.
hinge pin into cover, snapping into clip at same time (FIG 5-D).
NOTE: To remove hinge pin, support
access cover and apply force to corner of hinge pin as shown FIG 5-E.
unit and its individual shut-off valve from gas supply line during any
pressure testing of system in excess of ½ PSIG (3.4 kPa, 14” water column
[W.C.]). DO NOT set inlet pressure higher than maximum indicated on rating
plate of gas valve (13” W.C.). Isolate unit from gas supply line by
closing its individual manual shutoff valve during any pressure testing
< ½ psig.
FIRE AND/OR EXPLOSION
Do not use matches, candles or other
sources of ignition when checking for gas leaks.
on gas and check water heater and all connections for gas leaks with leak
water heater tank, check all connections for water leaks (FIG 1- A&B).
RELIEF VALVE – (FIG 10)
Valve is not serviceable, it must
Tampering with valve will result
in scalding injury.
Tampering with valve will void
DO NOT place a valve, plug or
reducing coupling on outlet part of pressure temperature relief valve.
THIS VALVE IS A SAFETY COMPONENT
AND MUST NOT BE REMOVED FOR ANY REASON OTHER THAN REPLACEMENT. This water
heater is equipped with a temperature and pressure relief valve that complies
with standard for Relief Valves and Automatic Gas Shutoff Devices for Hot Water
Systems, ANSI Z21.22.
If you use a discharge line, do
not use a reducing coupling or other restriction smaller than outlet of relief
valve. Allow complete drainage of both valve and line.
FOR REPLACEMENT PARTS:
DO NOT install anything less than
a combination temperature-pressure relief valve certified by a nationally
recognized testing laboratory that maintains periodic inspection of product of
listed equipment or materials, as meeting requirements for Relief Valves and
Automatic Gas Shutoff Devices for Hot Water Supply Systems, ANSE Z21.22. Valve
must have a maximum set pressure not to exceed 150 psi.
Install valve into opening
provided and marked for this purpose on water heater.
Installation must conform with
local codes or in the absence of local codes, American National Standard for
recreational Vehicles, ANSI A119.2/NFPA 50IC.
For external electrical source,
ground this unit in accordance with National Electrical Code ANSI/NFPA70.
Your Atwood gas water heater is
now ready for operation. Continue to HOW TO OPERATE YOUR WWATER HEATER.
Electronic Ignition continue to Electronic Ignition WIRING
Pilot Relight continue to Pilot Relight WIRING INSTRUCTIONS.
For Heat Exchange continue –
5/8” dia. or 2 or 3 coolant system hose with SAE 053 A Type “E” clamp
attached (FIG 6-E) onto heat exchanged tube as far as possible (FIG 6-B).
hose clamp and slide toward heat exchange unit past annular groove (FIG
6-C) and release.
to HOW TO OPERATE YOUR WATER HEATER and/or Electronic Ignition OPERATION.
For COMBINATION GAS/ELECTRIC
MODELS continue –
This water heater is designed to
operate with gas, electricity, or a combination of both.
Provide adequate clearance at rear
of unit for service of water connections and operation of manually re-setable
high temperature limit switch on combination gas/electric units.
GENERAL INSTALLATION instructions.
NOTE: All wiring must comply with
applicable electrical codes.
When using Romex with a bare earth
ground, take care to position ground wire so it does not contact the heating
Use electrical metallic tubing,
flexible, metal conduit, metal clad cable, or nonmetallic-sheathed cable with
grounding conductor. Wire must have a capacity of 1500 watts or greater. The
wiring method must conform to applicable sections of article 551 of National
Electrical Code ANSI/NFPA 70.
to Wiring Diagram. Make 120 VAC electrical connections from junction box
on back of unit.
hot lead to (1) Black.
common lead to (2) White.
ground wire from electrical service to (3) green ground lead in junction
box 3. Place switch in “OFF” position.
When a cord and plug connection to the power supply are used
on water heater, power chord must be UL listed as suitable for damp locations,
hard or extra hard usage. It must be a flexible cord such as type
S,SO,ST,STO,SJ,SJT,SJTO,HS, or HSO cord as described in National Electrical Code,
ANSI/NFPA 70. The length of an external cord to water heater, measured to face
of attachment plug, shall be no less than 2 feet not more than 6 feet. Supply
cord must be a minimum of 14 AWG and attachment plug must be rated at 15 amps.
Label all wires before disconnecting when servicing
Verify proper operation after servicing.
Operation using gas continue to HOW TO OPERATE YOUR WATER
HEATER, electrically continue to COMBINATION Gas/Electric OPERATION.
ELECTRONIC IGNITION – WIRING INSTRUCTIONS
unit according to GENERAL INSTALLATION instructions.
NOTE: It is recommended unit be
connected directly to a 12V DC battery or to filtered side of an AC/DC
converter. Avoid connections to unfiltered side of an AC/DC converter whenever
possible. Use a minimum of 18 gauge wire, UL and CSA listed.
Refer to WIRING DIAGRAM. Install
remote switch in a convenient location. Position wall plate with letters up.
Before making connections turn switch OFF. The switch is off when the button is
depressed towards terminal see wiring diagram.
lead to switch terminal (6) on indicator light of switch
(4) on indicator light of switch to negative battery terminal
lead to negative battery terminal
lead on water heater to terminal (3) on switch
2 on switch to positive battery terminal.
ELECTRONIC IGNITION OPERATION
PILOT RELIGHT – WIRING
unit according to GEWNERAL INSTALLATION instructions.
to Wiring Diagram. Use 18 gauge wire, UL/CSA listed.
PILOT & PILOT RELIGHT OPERATIONS.
DO NOT store or use gasoline or
other flammable vapors and liquids in the vicinity of this or any other
Should overheating occur, or gas
supply fail to shut off, turn OFF manual gas control valve to appliance, or
turn gas OFF at the LP tank. On ELECTRONIC IGNITION MODEL turn operating switch
to OFF position and remove red wire from left hand terminal of ECO switch or
turn gas OFF at the LP tank.
Use with LP gas only.
Shut off gas appliances and pilot lights when refueling.
On PILOT RELIGHT MODELS, turn off
the ignition module when refueling gasoline tanks or LP tanks.
Turn gas OFF at the LP tank when
vehicle is in motion. This disables all gas appliances and pilot lights. Gas
appliances must never be operated while vehicle is in motion. Unpredictable
wind currents may be created which could cause flame reversal in the burner
tube, which could result in fire damage. The thermal cut off fuse could also be
unnecessarily activated resulting in a complete shutdown of the water heater
requiring replacement of the thermal cut off. See maintenance of electroning
ignition water heaters for further explanation of the thermal cut off.
LP tanks must be filled by a
qualified gas supplier only.
TO OPERATE YOUR WATER HEATER
Do not smoke or have any flame
near an open faucet.
If water heater has not been used
for more than two weeks, hydrogen gas may form in water line. Under these
conditions to reduce the risk of injury, open hot water faucet for several
minutes art kitchen sink before you use any electrical appliance connected to
hot water system.
If hydrogen gas is present, you
probably hear sounds like air escaping through the pipe as water begins to
Do not tamper with pilot orifice.
Do not operate without water in tank.
gas control valve knob (FIG 7-B or FIG 8-B) to OFF position.
at least five minutes to allow accumulated gas in burner compartment to
heater may be equipped with a White Rodgers or Robertshaw Unitrol Control.
FOR WHITE RODGERS CONTROL (FIG 7)
lighting control knob (FIG 7-B) to PILOT position and hold against stop
while lighting pilot burner (FIG 9-D).
pilot to burn 30 seconds then release lighting control knob.
lighting control knob (FIG 7-B) to ON position.
pilot does not remain lit, repeat operation allowing longer period before
releasing lighting control knob.
temperature selection lever (FIG 7-A) at mark between warm and hot
FOR A ROBEERTSHAW UNITROL (FIG 8)
lighting control dial (FIG 8-B) to PILOT position.
and hold reset push button (FIG 8-A) while lighting pilor burner (FIG 9-D).
pilot to burn 30 seconds before releasing reset push button.
pilot does not remain lit, repeat operation allowing longer period before
releasing reset push button.
lighting control dial (FIG 8-B) to ON position.
temperature control dial (FIG 8-C) at mid-point position between warm and hot.
complete shut down and before servicing, turn gas control knob (FIG 7-B or
FIG 8-b) to OFF position When water heater is not in use set temperature
control lever (White Rodgers) or dial (Robertshaw) to lowest possible
control dial at a a higher position will produce excessively hot water.
The temperature knob or lever is factory adjusted to its
lowest dial setting. We recommend the mid-point position between warm and hot,
as noted above. This will provide for energy efficient operation and sufficient
hot water. Valves fro reducing point of use temperature by mixing cold and hot
water are available. Consult a licensed plumber or local plumbing authority.
Adjust Main Burner (FIG 9):
air shutter screw (FIG 9-A).
air shutter (FIG 9-B) to right until some yellow appears in main burner
air shutter (FIG 9-B) to left until yello9w disappears.
air shutter screw (FIG 9-A).
Read MAINTENANCE AND CARE INSTRUCTIONS
ELECTRONINC IGNITION OPERATION
to WIRING DIAGRAM. Place remote switch in ON position.
remote switch light stays on longer than 15 seconds, place remote switch
in OFF position and wait 5 minutes.
complete shut-down and before servicing:
remote switch in OFF position.
red wire from left hand terminal of ECO switch (ECO to valve).
heater fails to operate due to high water temperature, a lockout condition
occurs (indicator light on). After water cools, reset switch in OFF
position for at least 30 seconds, then turn to ON position.
- If a
lockout condition persists contact an Atwood Service Center.
Read MAINTENANCE AND CARE INSTRUCTIONS & ELECTRONIC
PILOT RELIGHT OPERATION
the switch located on the spark module to the ON position.
PILOT OPERATION instructions.
complete shut down, turn lighting control knob on thermostat and spark
module switch to OFF position.
Read MAINTENANCE AND CARE INSTRUCTIONS
COMBO gas/electric ELECTRIC OPERATION
gas operation refer to Pilot, Pilot Relight, or Electronic Ignition
OPERATION section (as applicable).
electrical operation use switch at the rear of water heater.
fill tank with water.
switch ON (FIG 11-B) (located at rear of water heater).
NOTE: Turning power on to heater
without water covering heating element may burn out element and void warranty.
for proper operation. Water temperature is set at 140 degrees F.
- If the
manual reset high temperature limit switch should operate, reset switch
(FIG 11-A) by depressing with pencil or other nonmetallic object. If still
experiencing problems contact an authorized Atwood Service Center or
Atwood Service Department.
Read MAINTENANCE AND CARE
AND CARE INSTRUCTIONS
SERVICE CALLS & QUESTIONS
Location and phone numbers of
qualified Service Centers can be found at our website http://www.atwoodmobile.com or call
574-264-2131 to have a Service Center List mailed.
FIRE OR EXPLOSION
Shut off gas supply at LP
container before disconnecting a gas line.
Keep control compartment clean and
free of gasoline, combustible material, and flammable liquids and vapors.
AFTERMARKET WATER HEATING ELEMENT
DO NOT alter water heater, it will
DO NOT USE aftermarket heating
elements, they can lack critical safety controls.
Use of aftermarket heating
elements can lead to an out of control heating of water tank and a catastrophic
wet side explosion.
The use of any aftermarket heating
element devices may also result in damage to components or water heater. Atwood’s
written warranty states – “failure or damage resulting from any alteration to
our water heater is the owner’s responsibility”. Any alteration, like the
addition of an aftermarket heating element device, will void the warranty.
LP and Water system must be turned
Have gas pressure tested
periodically. Should be set at 11 inches of water column with three appliances
Drain water heater at regular
intervals (at least one time during the year).
Drain water hearer before storing
RV for the winter or when the possibility of freezing exists.
Keep vent and combustion air grill
clear of obstructions.
Periodically, compare flame of
main and pilot burners with FIG 9 and main burner adjustments in HOW TO OPERATE
YOUR WATER HEATER.
When water heater is not in use
set temperature control lever (White Rodgers) or dial (Robertshaw) to lowest
possible position. This will reduce the effects of low outdoor temperatures on
calibration of temperature control mechanism.
Presence of soot indicates the
need to adjust flue.
ELECTRONIC IGNITION MAINTNENANCE
This water heater comes
factory-equipped with a fused circuit-board, which will protect the circuit
board from wiring shorts. If the fuse should activate, the water heater will
not operate. Before replacing the fuse, check for a short external to the
board. Once the short is corrected, replace the 2 amp fuse with a mini ATO
style fuse. DO NOT install a fuse larger than 3 amps.
If the fuse is good and the unit
is inoperative, check for excessively high voltage to the unit (more than 14
If the previous two steps did not
solve the problem, check the thermal cut-off. The thermal cutoff is a device
installed in the power supply line. This device will shut off electrical power
and stop heater operation when activated. For example, if an obstruction within
the flue tube should occur, such as described above in the Preventative
maintenance section, the burner flame/heat may contact the cutoff. In order to
restore power and proper operation of the water heater, the obstruction must be
removed and the thermal cutoff must be replaced.
Spiders, mud wasps, and other
insects can build nests in burner tube. This causes poor combustion, delayed
ignition outside combustion tube. Listen for a change in burner sounds or in
flame appearance from a hard blue flue flame to a soft lazy flame or one that
is very yellow. These are indications of an obstruction in burner tube (FIG
9-C). Inspect and clean on a regular basis.
air shutter screw (FIG 9-A) and slide air shutter (FIG 9-B) down burner
a flexible wire brush down burner tube (FIG 9-C) until it is visible at
end of burner tube.
burner where it enters combustion tube.
air shutter to original position and replace screw.
orifice, burner tube and shutter must be aligned so that the shutter is
not binding on the air tube.
HOW TO CLEAN PILOT MODELS
main burner orifice and pilot assembly for contamination (dirt, spider
main burner tube with small brush.
burner adjustment- open air shutter ¼ way.
pilot flame. Check for contamination – if clean have the pilot orifice
HOW TO CLEAN ELECTRONIC IGNITION MODEL
main burner orifice.
and adjust main burner.
burner and valve manifold must align with each other.
electrode for cracked porcelain.
electrode for proper gap – 1/8” between electrode and ground.
module board functions intermittently, remove board and clean terminal
block with pencil eraser.
WATER HEATER TANK CARE
Turn off water heater and allow
time for water to cool before removing drain plug to flush tank.
To insure the best performance of
your water heater and add to the life of the tank, periodically drain and flush
the water heater tank. Before long term storage or freezing weather drain and
flush the tank.
off main water supply (the pump or water hook up source).
Water Heater Tank by removing the drain plug. If the water flows
sporadically or trickles instead of a steady stream of water, we recommend
the following action; first open the Pressure Temperature Relief Valve to
allow air into the tank and secondly, take a small gauge wire or coat
hanger and poke through the drain opening to eliminate any obstructions.
draining the tank, because of the placement of the Drain Plug,
approximately two quarts of water will remain in the tank. This water
contains most of the harmful corrosive particles. To remove these harmful
corrosive particles flush the tank with either air or water. Whether using
air or water pressure, it may be applied through the inlet or outlet on
the rear of the tank of the Pressure Temperature Relief Valve. (If using
the Pressure Temperature Relief Valve the Support Flange must be removed).
The pressure will force out the remaining water and the corrosive
If you use water pressure, pump
fresh water into the tanks with the assistance of the on-board pump or use
external water for 90 seconds to allow the fresh water to agitate the stagnant
water on the bottom of the tank and force deposits through the drain opening.
Continue repeating adding water and draining until the particles have been
cleared from the water remaining in the tank.
Replace the Drain Plug and close the Pressure
Tepmerature Relieve Valve. The approximately two quarts of water rermaining on
the tank after draining will not cause damage to the tank should freezing
Do not place a valve, plug or
reducing coupling on outlet part of pressure-temperature relief valve.
A pressure Temperature Relief
Valve, dripping while the water heater is running, DOES NOT mean it is
defective. During normal expansion of water, as heated in the closed water
system of a recreation vehicle, the Pressure Temperature Relief Valve will
sometimes drip. The Atwood water heater tank is designed with an internal air
gap at the top of the tank to reduce the possibilityof dripping. In time, the
expanding water will absorb this air and it must be restored.
Turn off water heater before
opening pressure-temperature relief valve to establish air space. Storage water
must be cool.
REPLACE AIR GAP FOLLOW THESE STEPS:
1. Turn off main water supply (the pump or water hook up source).
2. Let water cool or let run until
3. Open the hot water faucet
closest to the water heater.
4. Pull handleof pressure
temperature relief valve straight out and allow water to flow until it stops.
5. Allow pressure temperature
relief valve to snap shut; close faucet; turn on water supply.
6. Turn on water heater and test.
* At least once a year manually
operate pressure temperature relief valve.
When pressure temperature relief
valve discharges again, repeat above procedure. For a permanent solution, we
recommend one of the following:
*Install a pressure relief valve in
cold water inlet line to water heater and attach a drain line from valve to
outside of coach. Set to relieve at 100-125 PSI.
Install a diaphragm-type expansion tank in cold
water inlet line. Tank should be sized to allow for expansion of approximately
15oz. Of water and per-charged to a pressure equal to water supply pressure.
These devices can be obtained from a plumbing contractor or service center.
TO REMOVE UNPLEASANT ODOR
A rotten egg odor (hydrogen
sulfide) may be produced when the electro galvanic action of the cladding
material releases hydrogen from the water. If sulfur is present on the water
supply the two will combine and produce an unplesant smell.
1. Turn off main water supply.
Drain the water heater tank and reinstall rain plug. Remove the pressure
temperature relief valve. Mix solution of 4 parts white vinegar to 2 parts
water. With a funnel, carefully poor solution into tank.
2. Cycle water heater with the
above solution, letting it run under normal operation 4-5 times.
3. Remove the drain plug anf
thoroughly drain all water from the tank. Flush the water heater to remove any
sediment. You may flush the tank with air pressure or fresh water. Pressure may
be applied through either the inlet or outlet valves on the rear of the tank or
through the pressure temperature relief valve coupling located on the front of
TO FLUSH TANK WITH WATER PRESSURE:
Fresh water should be pumped into
the tank with either the onboard pump or external water pressure. Continue this
flushing process for approximatley 5 minutes, allowing the fresh water to
agitate the stagnant water on the bottom of the tank and forcing the
deposits through the drain openinig.
4. replace drain plug and pressure
temperature relief valve.
5. Refill tank with fresh water the
contains no sulphur.
The Atwood water heater is designed for use in a
recreation vehicle. If you use your vehicle frequently or for long periods of
time, flushing the water heater several times a year will prolong the life of
the storage tank.