Desa GWRP16 Original instructions

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WARNING: If the information in this manual is not
followedexactly,afireorexplosionmayresultcaus-
ing property damage, personal injury, or loss of life.
— 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
• Do not try to light any appliance.
• Donottouchanyelectricalswitch;donotuseany
phone in your building.
• Immediately call your gas supplier from a
neighbor’s phone. Follow the gas supplier’s in-
structions.
• Ifyoucannot reach yourgassupplier,callthe fire
department.
— Installation and service must be performed by a
qualified installer, service agency, or the gas
supplier.
WARNING: Improper installation,
adjustment,alteration,service,or
maintenance can cause injury or
property damage. Refer to this
manualforcorrectinstallationand
operational procedures. For as-
sistanceoradditionalinformation
consult a qualified installer, ser-
vice agency, or the gas supplier.
WARNING: This is an unvented
gas-fired heater. It uses air (oxy-
gen) from the room in which it is
installed. Provisions for ad-
equate combustion and ventila-
tion air must be provided. Refer
to AirforCombustionandVenti-
lation section on page 4 of this
manual.
This appliance may be installed in an aftermarket*, permanently located, manufactured
(mobile) home, where not prohibited by local codes.
This appliance is only for use with the type of gas indicated on the rating plate. This
appliance is not convertible for use with other gases.
*Aftermarket: Completion of sale, not for purpose of resale, from the manufacturer
Save this manual for future reference.
Save this manual for future reference.
GWRP16, GWRN18
GWRP26, GWRN30
GWRP16T, GWRN18T
GWRP26T, GWRN30T
TM
UNVENTED (VENT-FREE)
INFRARED GAS HEATER
SAFETY INFORMATION AND INSTALLATION MANUAL

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TABLE OF CONTENTS
SAFETY INFORMATION
WARNING ICON G 001
WARNINGS
IMPORTANT: Read this owner’s manual carefully and
completely before trying to assemble, operate, or ser-
vice this heater. Improper use of this heater can cause
serious injury or death from burns, fire, explosion,
electrical shock, and carbon monoxide poisoning.
DANGER: Carbon monoxide poisoning may lead
to death!
WARNING: Any change to this heater or its
controls can be dangerous.
1. This appliance is only for use with the type of gas indicated on
the rating plate. This appliance is not convertible for use with
other gases.
2. Do not place propane/LP supply tank(s) inside any structure.
Locate propane/LP supply tank(s) outdoors.
3. This heater shall not be installed in a bedroom or bathroom.
Do not place clothing or other flammable material on
ornearthe appliance. Neverplaceanyobjects on the
heater.
Surface of heater becomes very hot when running
heater. Keep children and adults away from hot sur-
face to avoid burns or clothing ignition. Heater will
remainhotforatimeaftershutdown.Allowsurfaceto
cool before touching.
Carefully supervise young children when they are in
the same room with heater.
Make sure grill guard is in place before running
heater.
Keeptheappliancearea clear and free from combus-
tible materials, gasoline and other flammable vapors
and liquids.
WARNING: Do not use any accessory not ap-
proved for use with this heater.
Carbon Monoxide Poisoning: Early signs of carbon monoxide
poisoningresemble the flu, with headaches, dizziness, ornausea. If
you have these signs, the heater may not be working properly. Get
fresh air at once! Have heater serviced. Some people are more
affected by carbon monoxide than others. These include pregnant
women,peoplewithheartorlungdiseaseoranemia,thoseunderthe
influence of alcohol, and those at high altitudes.
Natural and Propane/LP Gas: Natural and propane/LP gases are
fuelgases.Fuelgasesareodorless.Anodor-makingagentareadded
to fuel gases. The odor helps you detect a fuel gas leak. However,
the odor added to fuel gas can fade. Fuel gas may be present even
though no odor exists.
Make certain you read and understand all warnings. Keep this
manual for reference. It is your guide to safe and proper operation
of this heater.
Due to high temperatures, the appliance should be
located out of traffic and away from furniture and
draperies.
SAFETY INFORMATION
TABLE OF CONTENTS
SAFETY INFORMATION ............................................................ 2
LOCAL CODES........................................................................... 3
PRODUCT IDENTIFICATION ..................................................... 3
UNPACKING ............................................................................... 3
PRODUCT FEATURES .............................................................. 3
AIR FOR COMBUSTION AND VENTILATION ........................... 4
INSTALLATION ........................................................................... 7
OPERATING HEATER.............................................................. 13
INSPECTING HEATER............................................................. 16
CLEANING AND MAINTENANCE ............................................ 17
SPECIFICATIONS .................................................................... 18
TROUBLESHOOTING .............................................................. 19
ILLUSTRATED PARTS BREAKDOWNAND PARTS LIST ....... 22
REPLACEMENT PARTS .......................................................... 26
SERVICE HINTS....................................................................... 26
TECHNICAL SERVICE ............................................................. 26
SERVICE PUBLICATIONS ....................................................... 26
ACCESSORIES ........................................................................ 26
OWNER’S REGISTRATION FORM.......................................... 27
PARTS CENTRALS .................................................................. 29
WARRANTY INFORMATION...................................... Back Cover

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3
SAFETY INFORMATION
LOCAL CODES
PRODUCT IDENTIFICATION
UNPACKING
PRODUCT FEATURES
4. If you smell gas
• Shut off gas supply
• Do not try to light any appliance
• Do not touch any electrical switch; do not use any phone in
your building
• Immediately call your gas supplier from a neighbor’s phone.
Follow the gas supplier’s instructions
• If you cannot reach your gas supplier, call the fire department
5. Always run heater with plaque control knob at the 1, 2, 3, or 4
lockedpositions. Neverset controlknob between locked positions.
Poorcombustionandhigherlevelsofcarbonmonoxidemayresult.
6. This heater needs fresh, outside air ventilation to run properly.
This heater has an Oxygen Depletion Sensing (ODS) safety
shutoff system. The ODS shuts down the heater if not enough
fresh air is available. See Air for Combustion and Ventilation,
pages 4 through 6.
7. If heater shuts off, do not relight until you provide fresh, out-
side air. If heater keeps shutting off, have it serviced.
8. Do not run heater
• where flammable liquids or vapors are used or stored
• under dusty conditions
9. Do not use heater if any part has been under water. Immedi-
ately call a qualified service technician to inspect the room
heater and to replace any part of the control system and any
gas control which has been under water.
10. Turn off and unplug heater and let cool before servicing. Only
a qualified service person should service and repair heater.
11. Operating heater above elevations of 4,500 feet could cause
pilot outage.
12. To prevent performance problems, do not use propane/LP fuel
tank of less than 100 lbs. capacity.
13. Before using furniture polish, wax, carpet cleaner, or similar
products, turn heater off. If heated, the vapors from these prod-
ucts may create a white powder residue within burner box or
on adjacent walls or furniture.
14. Provide adequate clearances around air openings.
SAFETY INFORMATION
Continued
PRODUCT IDENTIFICATION
LOCAL CODES
Installanduseheaterwithcare. Follow all local codes. In theabsence
oflocalcodes,usethelatesteditionofNationalFuelGasCode, ANSI
Z223.1/NFPA 54*.
*Available from:
American National Standards Institute, Inc.
1430 Broadway
New York, NY 10018
National Fire Protection Association, Inc.
Batterymarch Park
Quincy, MA 02269
Figure 1 - Vent-Free Gas Heater
UNPACKING
1. Remove heater from carton.
2. Removeall protectivepackaging applied toheater forshipment.
3. Check heater for any shipping damage. If heater is damaged,
promptly inform dealer where you bought heater.
Ignitor Button Control Knob
Heater
Cabinet
Front
Panel
Plaque
Grill
Guard
PRODUCT FEATURES
SAFETY DEVICE
This heater has a pilot with an Oxygen Depletion Sensing (ODS)
safety shutoff system. The ODS/pilot is a required feature for vent-
free room heaters. The ODS/pilot shuts off the heater if there is not
enough fresh air.
PIEZO IGNITION SYSTEM
This heater has a piezo ignitor. This system requires no matches,
batteries, or other sources to light heater.
THERMOSTATIC HEAT CONTROL
(Thermostat Models Only)
Thermostat models have a thermostat sensing bulb and a control
valve.Thisresultsinthegreatestheatercomfort.Thiscanalsoresult
in lower gas bills.

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AIR FOR COMBUSTION AND
VENTILATION
Today’s homes are built more energy efficient than ever. New
materials, increased insulation, and new construction methods help
reduce heat loss in homes. Home owners weather strip and caulk
around windows and doors to keep the cold air out and the warm air
in.Duringheatingmonths,homeownerswanttheirhomesasairtight
as possible.
While it is good to make your home energy efficient, your home
needs to breathe. Fresh air must enter your home. All fuel-burning
appliances need fresh air for proper combustion and ventilation.
Exhaustfans,fireplaces,clothesdryers,andfuelburningappliances
drawairfromthehousetooperate.Youmustprovideadequatefresh
air for these appliances. This will insure proper venting of vented
fuel-burning appliances.
PROVIDING ADEQUATE VENTILATION
The following are excerpts from National Fuel Gas Code, ANSI
Z223.1/NFPA 54, Section 5.3, Air for Combustion and Ventilation.
All spaces in homes fall into one of the three following ventilation
classifications:
1. Unusually Tight Construction
2. Unconfined Space
3. Confined Space
The information on pages 4 through 6 will help you classify your
space and provide adequate ventilation.
Unusually Tight Construction
The air that leaks around doors and windows may provide enough
fresh air for combustion and ventilation. However, in buildings of
unusually tight construction, you must provide additional fresh air.
WARNING: This heater shall not be installed in a
confined space or unusually tight construction un-
lessprovisionsareprovidedforadequatecombustion
and ventilation air. Read the following instructions to
insure proper fresh air for this and other fuel-burning
appliances in your home.
Unusually tight construction is defined as construction
where:
a. walls and ceilings exposedtotheoutsideatmosphere
have a continuous water vapor retarder with a rating
of one perm (6x10-11 kg per pa-sec-m2) or less with
openings gasketed or sealed and
b. weather stripping has been added on openable win-
dows and doors
and
c. caulking or sealants are applied to areas such as
joints around window and door frames,between sole
platesandfloors,betweenwall-ceilingjoints,between
wall panels, at penetrations for plumbing, electrical,
and gas lines, and at other openings.
If your home meets all of the three criteria above, you
must provide additional fresh air. See Ventilation Air
From Outdoors , page 6.
Ifyourhomedoes not meet all of the threecriteriaabove,
proceed to Determining Fresh-Air Flow For Heater Loca-
tion , page 5.
Confined and Unconfined Space
The National Fuel Gas Code, ANSI Z223.1/NFPA 54 defines a
confined space as a space whose volume is less than 50 cubic feet
per 1,000 Btu per hour (4.8 m3per kw) of the aggregate input rating
of all appliances installed in that space and an unconfined space as
aspacewhosevolumeisnotlessthan50cubicfeetper1,000Btuper
hour (4.8 m3per kw) of the aggregate input rating of all appliances
installed in that space. Rooms communicating directly with the
space in which the appliances are installed*, through openings not
furnishedwithdoors,are considered apartoftheunconfined space.
* Adjoining rooms are communicating only if there are doorless
passageways or ventilation grills between them.
AIR FOR COMBUSTION AND VENTILATION
Providing Adequate Ventilation

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AIR FOR COMBUSTION AND
VENTILATION
Continued
DETERMINING FRESH-AIR FLOW FOR
HEATER LOCATION
Determining if You Have a Confined or
Unconfined Space
Usethis worksheet to determineif youhavea confinedorunconfined space.
Space:Includestheroominwhichyouwillinstallheaterplusanyadjoining
rooms with doorless passageways or ventilation grills between the rooms.
1. Determine the volume of the space (length x width x height).
Length x Width x Height = ___________ cu. ft. (volume of space)
Example: Space size 20 ft. (length) x 16 ft. (width) x 8 ft. (ceiling
height) = 2560 cu. ft. (volume of space)
Ifadditional ventilationto adjoiningroomis suppliedwith grills oropen-
ings, add the volume of these rooms to the total volume of the space.
2. Multiply the space volume by 20 to determine the maximum Btu/Hr
the space can support.
__________ (volume of space) x 20 = (Maximum Btu/Hr the space
can support)
Example: 2560 cu. ft. (volume of space) x 20 = 51,200 (maximum
Btu/Hr the space can support)
3. Add the Btu/Hr of all fuel burning appliances in the space.
Vent-free heater _____________ Btu/Hr
Gas water heater* _____________ Btu/Hr
Gas furnace _____________ Btu/Hr
Vented gas heater _____________ Btu/Hr
Gas fireplace logs _____________ Btu/Hr
Other gas appliances* + _____________ Btu/Hr
Total = _____________ Btu/Hr
* Do not include direct-vent gas appliances. Direct-vent draws com-
bustion air from the outdoors and vents to the outdoors.
Example:
Gas water heater _____________ Btu/Hr
Vent-free heater + _____________ Btu/Hr
Total = _____________ Btu/Hr
WARNING: If the area in which the heater may be
operated is smaller than that defined as an uncon-
fined space or if the building is of unusually tight
construction,provideadequatecombustionandven-
tilation air by one of the methods described in the
National Fuel Gas Code, ANSI Z223.1/NFPA 54 Sec-
tion 5.3 or applicable local codes .
4. Compare the maximum Btu/Hr the space can support with the actual
amount of Btu/Hr used.
__________________ Btu/Hr (maximum the space can support)
__________________ Btu/Hr (actual amount of Btu/Hr used)
Example: 51,200 Btu/Hr (maximum the space can support)
60,000 Btu/Hr (actual amount of Btu/Hr used)
Thespaceinthe above example is a confined space because the actual Btu/
HrusedismorethanthemaximumBtu/Hrthespacecansupport.You must
provide additional fresh air. Your options are as follows:
A. Rework worksheet, adding the space of an adjoining room. If the ex-
tra space provides an unconfined space, remove door to adjoining
roomoradd ventilation grills between rooms. See VentilationAirFrom
Inside Building, page 6.
B. Vent room directly to the outdoors. See Ventilation Air From Out-
doors, page 6.
C. Install a lower Btu/Hr heater, if lower Btu/Hr size makes room un-
confined.
If the actual Btu/Hr used is less than the maximum Btu/Hr the space can
support, the space is an unconfined space. You will need no additional fresh
air ventilation.
40,000
20,000
60,000
AIR FOR COMBUSTION AND VENTILATION
Determining Fresh-Air Flow For Heater Location

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Figure 3 - Ventilation Air from Outdoors
AIR FOR COMBUSTION AND
VENTILATION
Continued
VENTILATION AIR
Ventilation Air From Inside Building
This fresh air would come from an adjoining unconfined space.
When ventilating to an adjoining unconfined space, you must
provide two permanent openings: one within 12" of the ceiling and
one within 12" of the floor on the wall connecting the two spaces
(see options 1 and 2, Figure 2). You can also remove door into
adjoining room (see option 3, Figure 2). Follow the National Fuel
Gas Code, ANSI Z223.1/NFPA 54, Section 5.3, Air for Combustion
and Ventilation for required size of ventilation grills or ducts.
Ventilation Air From Outdoors
Provideextrafresh airbyusingventilationgrillsorducts.Youmust
provide two permanent openings: one within 12" of the ceiling and
one within 12" of the floor. Connect these items directly to the
outdoorsorspacesopentotheoutdoors.Thesespacesincludeattics
and crawl spaces. Follow the National Fuel Gas Code, ANSI
Z223.1/NFPA 54, Section 5.3, Air for Combustion and Ventilation
for required size of ventilation grills or ducts.
IMPORTANT: Do not provide openings for inlet or outlet air into
attic if attic has a thermostat-controlled power vent. Heated air
entering the attic will activate the power vent.
Figure 2 - Ventilation Air from Inside Building
AIR FOR COMBUSTION AND VENTILATION
Ventilation Air
Outlet
Air Ventilated
Attic
Outlet
Air
Inlet
Air
Inlet Air Ventilated
Crawl Space
To
Crawl
Space
To Attic
Or
Remove
Door into
Adjoining
Room,
Option 3
Ventilation Grills
Into Adjoining Room,
Option 2
12"
12"
Ventilation
Grills
into Adjoining
Room,
Option 1

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7
INSTALLATION
WARNING: A qualified service person must in-
stall heater. Follow all local codes.
CHECK GAS TYPE
Useonlythe correct typeofgas (natural orpropane/LP).Ifyour gas
supply is not the correct gas type, do not install heater. Call dealer
where you bought heater for proper type heater.
INSTALLATION ITEMS
Beforeinstallingheater,make sure youhavetheitemslisted below.
• for propane/LP gas, external regulator (supplied by installer)
• piping (check local codes)
• sealant (resistant to propane/LP gas)
• equipment shutoff valve *
• ground joint union
• sediment trap
• tee joint
• pipe wrench
• for natural gas, test gauge connection*
* A CSA design-certified equipment shutoff valve with 1/8" NPT
tap is an acceptable alternative to test gauge connection. The
optional CSA design-certified equipment shutoff valve can be
purchased from your dealer. See Accessories, page 26.
NOTICE: This heater is intended for use as supple-
mental heat. Use this heater along with your primary
heating system. Do not install this heater as your
primary heat source. If you have a central heating
system, you may run system’s circulating blower
while using heater. This will help circulate the heat
throughoutthehouse.Intheeventofapoweroutage,
you can use this heater as your primary heat source.
CAUTION: This heater creates warm air currents.
Thesecurrentsmoveheattowallsurfacesnexttoheater.
Installing heater next to vinyl or cloth wall coverings or
operating heater where impurities (such as, but not
limited to, tobacco smoke, aromatic candles, cleaning
fluids, oil or kerosene lamps, etc.) in the air exist, may
discolor walls or cause odors.
WARNING: Never install the heater
•in a bedroom or bathroom
•in a recreational vehicle
•where curtains, furniture, clothing, or other flam-
mable objects are less than 36 inches from the
front, top, or sides of the heater
•as a fireplace insert
•in high traffic areas
•in windy or drafty areas
LOCATING HEATER
This heater is designed to be mounted on a wall.
WARNING: Maintain the minimum clearances
shown in Figure 4. If you can, provide greater clear-
ances from floor, ceiling, and joining wall.
You can locate heater on floor, away from a wall. An optional floor
mounting stand is needed. Purchase the floor mounting stand from
your dealer. See Accessories, page 26.
INSTALLATION
Check Gas Type
Installation Items
Locating Heater
CAUTION:Ifyouinstalltheheaterinahomegarage
•heater pilot and burner must be at least 18 inches
above floor
•locate heater where moving vehicle will not hit it
IMPORTANT: Vent-free heatersadd moistureto theair. Although
this is beneficial, installing heater in rooms without enough venti-
lation air may cause mildew to form from too much moisture. See
Air for Combustion and Ventilation, pages 4 through 6. If high
humidity is experienced, a dehumidifier may be used to help lower
the water vapor content in the air.
For convenience and efficiency, install heater
• where there is easy access for operation, inspection, and service
• in coldest part of room
An optional fan kit is available from your dealer. See Accessories,
page26.Ifplanningtousefan,locateheaternearanelectricaloutlet.
Figure4-MountingClearancesAsViewedFromFrontofHeater
Minimum
From
Sides Of
Heater
36"
2"
FLOOR
CEILING
Minimum
Minimum To
Top Surface
Of Carpeting,
Tile Or Other
Combustible
Material
Left
Side Right
Side
10"

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THERMOSTAT SENSING BULB
(Thermostat Models Only)
Thethermostatsensing bulbhasbeenplacedinsidetheheaterfor
protection during shipping.
Locating Thermostat Sensing Bulb (for Thermostat
Applications)
1. Remove front panel of heater (see Figure 7).
2. Locate thermostat sensing bulb just under burner assembly.
IMPORTANT: Attachthermostatsensingbulbtobackofheaterfor
proper operation.
Attaching Thermostat Sensing Bulb
1. Remove thermostat sensing bulb from holders inside heater.
Route through slot opening in bottom of heater.
2. Place clamp on thermostat sensing bulb as shown in Figure 5.
Clamp is provided in hardware package.
3. Snap clamp into upper mounting hole as shown in Figure 5.
Mounting hole is located on lower left edge on back of heater.
Make sure the thermostat sensing bulb is pointing up.
INSTALLATION
Continued
INSTALLATION
Thermostat Sensing Bulb
Installing Heater To Wall
INSTALLING HEATER TO WALL
Mounting Bracket
Locate mounting bracket in heater carton. Remove mounting bracket
from heater carton.
Figure 6 - Mounting Bracket
Figure 5 - Attaching Thermostat Sensing Bulb
Figure 7 - Removing Front Panel Of Heater
Removing Front Panel Of Heater
1. Remove the four painted screws, two on each side of front
panel.
2. Pull bottom of front panel forward, then out.
3. Remove any remaining packaging materials.
Methods For Attaching Mounting Bracket To Wall
Onlyuselastholeoneachendofmountingbrackettoattachbracket
to wall. These two holes are 14 inches apart from their centers.
Attach mounting bracket to wall in one of two ways:
1. Attaching to wall stud
2. Attaching to wall anchor
Attaching to Wall Stud: This method provides the strongest hold.
Insertmountingscrewsthroughmountingbracketandintowallstuds.
Attaching to Wall Anchor: This method allows you to attach
mounting bracket to hollow walls (wall areas between studs) or to
solid walls (concrete or masonry).
Decide which method better suits your needs. Either method will
provide a secure hold for the mounting bracket.
WARNING:Maintainminimumclearances shown
in Figure 8, page 9. If you can, provide greater clear-
ances from floor and joining wall.
Marking Screw Locations
1. Tape mounting bracket to wall where heater will be located.
Make sure mounting bracket is level.
Clamp
Thermostat Sensing Bulb

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INSTALLATION
Installing Heater To Wall (Cont.)
INSTALLATION
Continued
2. Mark screw locations on wall (see Figure 8).
Note: Only mark last hole on each end of mounting bracket.
Insert mounting screws through these holes only.
3. Remove tape and mounting bracket from wall.
Attaching Mounting Bracket To Wall
Note: Wallanchors,mountingscrews,andspacersareinhardware
package. The hardware package is provided with heater.
Attaching To Wall Stud Method
For attaching mounting bracket to wall studs
1. Drill holes at marked locations using 9/64" drill bit.
2. Place mounting bracket onto wall. Line up last hole on each
end of bracket with holes drilled in wall.
3. Insert mounting screws through bracket and into wall studs.
4. Tighten screws until mounting bracket is firmly fastened to
wall studs.
Figure 9 - Folding Anchor Figure 10 - Popping Open
Anchor Wings For Thin Walls
5 Plaque Heaters
3 Plaque Heater
14"
18 3/4"
Min.
12"
Min.
Adjoining Wall
Only Insert Mounting
Screws Through Last
Hole On Each End
Floor
Figure 8 - Mounting Bracket Clearances
18
3
/ 4 "
Min.
16"
Min. 14"
Adjoining Wall
Only Insert Mounting
Screws Through Last
Hole On Each End
Floor
Attaching To Wall Anchor Method
Forattachingmountingbrackettohollowwalls(wallareasbetween
studs) or solid walls (concrete or masonry)
1. Drill holes at marked locations using 5/16" drill bit. For solid
walls (concrete or masonry), drill at least 1" deep.
2. Fold wall anchor as shown in Figure 9.
3. Insertwallanchor(wingsfirst) into hole.Tapanchorflush to wall.
4. For thin walls (1/2" or less), insert red key into wall anchor.
Push red key to “pop” open anchor wings.
IMPORTANT: Do not hammer key!
For thick walls (over 1/2" thick) or solid walls, do not pop
open wings.
5. Place mounting bracket onto wall. Line up last hole on each
end of bracket with wall anchors.
6. Insert mounting screws through bracket and into wall anchors.
7. Tightenscrewsuntil mountingbracketis firmlyfastened to wall.
Placing Heater On Mounting Bracket
1. Locate two horizontal slots on back panel of heater.
2. Place heater onto mounting bracket. Slide horizontal slots onto
stand-out tabs on mounting bracket.
Figure 11 - Mounting Heater Onto Mounting Bracket
Mounting Bracket
(attached to wall)
Horizontal Slots
Stand-Out Tab

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Figure 12 - Installing Bottom Mounting Screws
Side View
Front View
Wall
Spacer
Heater
INSTALLATION
Continued
INSTALLATION
Installing Heater To Wall (Cont.)
Connecting To Gas Supply
Forpropane/LP gas, theinstaller mustsupplyan externalregulator.
Theexternalregulatorwillreduceincominggaspressure.Youmust
reduceincominggas pressure tobetween11and14inchesofwater.
Ifyoudonotreduceincominggaspressure,heaterregulatordamage
could occur. Install the external regulator with the vent pointing
downasshowninFigure13.Pointingtheventdownprotectsitfrom
freezing rain or sleet.
WARNING: A qualified service person must con-
nect heater to gas supply. Follow all local codes.
CAUTION: For propane/LP gas, never connect
heater directly to the propane/LP supply. This heater
requires an external regulator (not supplied). Install
the external regulator between the heater and pro-
pane/LP supply.
CAUTION: Use only new, black iron or steel pipe.
Internally-tinnedcoppertubingmaybeusedincertain
areas. Check your local codes. Use pipe of large
enoughdiametertoallowpropergasvolumetoheater.
If pipe is too small, undue loss of volume will occur.
WARNING: This appliance requires a 3/8" NPT
(National Pipe Thread) inlet connection to the pres-
sure regulator.
IMPORTANT :For natural gas, check gas line pressure before
connecting heater to gas line. Gas line pressure must be no greater
than 14 inches of water. If gas line pressure is higher, heater
regulator damage could occur.
WARNING:Fornaturalgas,never connect heater
to private (non-utility) gas wells. This gas is com-
monly known as wellhead gas.
CONNECTING TO GAS SUPPLY
Figure 13- External Regulator With Vent Pointing Down
External
Regulator
Propane/LP
Supply
Tank
Vent
Pointing
Down
Installing Bottom Mounting Screws
1. Locate two bottom mounting holes. These holes are near bot-
tom on back panel of heater (see Figure 12).
2. Mark screw locations on wall.
3. Remove heater from mounting bracket.
4. If installing bottom mounting screws into hollow or solid wall,
install wall anchors. Follow steps 1 through 4 under AttachingTo
Wall Anchor Method, page 9.
If installing bottom mounting screw into wall stud, drill holes
at marked locations using 9/64" drill bit.
5. Replace heater onto mounting bracket.
6. Place spacers between bottom mounting holes and wall anchor
or drilled hole.
7. Hold spacer in place with one hand. With other hand, insert
mounting screw through bottom mounting hole and spacer.
Place tip of screw in opening of wall anchor or drilled hole.
8. Tighten both screws until heater is firmly secured to wall. Do
not over tighten.
Note: Do not replace front panel at this time. Replace front
panel after making gas connections and checking for leaks (see
pages 11 and 12).

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11
INSTALLATION
Continued
INSTALLATION
Connecting To Gas Supply (Cont.)
Checking Gas Connections
Typical Inlet Pipe Diameters
GWRP16(T), GWRN18(T) - 3/8" or greater
GWRP26(T), GWRN30(T) - 1/2" or greater
Installation must include equipment shutoff valve, union, and
plugged 1/8" NPT tap. Locate NPT tap within reach for test gauge
hook up. NPT tap must be upstream from heater (see Figure 14).
IMPORTANT: Install an equipment shutoff valve in an accessible
location. The equipment shutoff valve is for turning on or shutting
off the gas to the appliance.
Apply pipe joint sealant lightly to male NPT threads. This will
prevent excess sealant from going into pipe. Excess sealant in pipe
could result in clogged heater valves.
Install sediment trap in supply line as shown in Figure 14. Locate
sedimenttrapwhere itiswithinreachforcleaning.Locatesediment
trap where trapped matter is not likely to freeze. A sediment trap
traps moisture and contaminants. This keeps them from going into
heatercontrols.Ifsedimenttrapisnotinstalledorisinstalledwrong,
heater may not run properly.
IMPORTANT: Hold the pressure regulator with wrench when
connecting it to gas piping and/or fittings. Do not over tighten pipe
connection to regulator. The regulator body could be damaged.
WARNING:Use pipe joint sealantthatisresistant
to liquid petroleum (LP) gas.
* A CSA design-certified equipment shutoff valve with 1/8" NPT
tap is an acceptable alternative to test gauge connection. Purchase
the optional CSA design-certified equipment shutoff valve from
your dealer. See Accessories, page 26.
Figure 14 - Gas Connection
Pressure Regulator
Tee Joint
Reducer
Bushing to
1/8" NPT
1/8" NPT
Plug Tap
Test
Gauge
Con-
nection*
Tee Joint
Pipe Nipple
Cap
Heater Cabinet
Sediment
Trap
Equipment
Shutoff Valve *
3"
Minimum
Natural Gas
From Gas Meter
(7" W.C. to 10.5" W.C.
Pressure)
Propane/LP
From External
Regulator
(11" W.C. to 14" W.C.
Pressure)
Regulator Bracket
3/8" NPT Pipe Nipple
Ground Joint Union
WARNING: Test all gas piping and connections
forleaksafterinstallingorservicing.Correctallleaks
at once.
WARNING: Never use an open flame to check for
aleak.Applyanoncorrosiveleakdetectionfluidtoall
joints.Bubblesformingshowaleak.Correctallleaks
at once.
CAUTION: For propane/LP gas, make sure exter-
nalregulator hasbeeninstalledbetweenpropane/LP
supply and heater. See guidelines under Connecting
to Gas Supply , page 10.
Pressure Testing Gas Supply Piping System
Test Pressures In Excess Of 1/2 PSIG (3.5 kPa)
1. Disconnect appliance with its appliance main gas valve (con-
trol valve) and equipment shutoff valve from gas supply pip-
ing system. Pressures in excess of 1/2 psig will damage heater
regulator.
2. Cap off open end of gas pipe where equipment shutoff valve
was connected.
3. Pressurize supply piping system by either opening propane/LP
supplytank valvefor propane/LP gasor openingmain gasvalve
located on or near gas meter for natural gas, or using com-
pressed air.
4. Check all joints of gas supply piping system.Apply a noncorrosive
leak detection fluid to all joints. Bubbles forming show a leak.
5. Correct all leaks at once.
6. Reconnect heater and equipment shutoff valve to gas supply.
Check reconnected fittings for leaks.
CHECKING GAS CONNECTIONS

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INSTALLATION
Continued
INSTALLATION
Checking Gas Connections (Cont.)
Figure 17 - Checking Gas Joints for Propane/LP Gas
Figure 15 - Equipment Shutoff Valve
Equipment
Shutoff
Valve
Propane/LP
Supply
Tank Thermostat
Gas Valve
ON
POSIT
O
PO
Open
Closed
Equipment
Shutoff
Valve
Figure 16 - Checking Gas Joints for Natural Gas
Equipment
Shutoff
Valve
Gas
Meter
Thermostat
Gas Valve
Test Pressures Equal To or Less Than 1/2 PSIG (3.5 kPa)
1. Close equipment shutoff valve (see Figure 15).
2. Pressurize supply piping system by either opening propane/LP
supplytank valvefor propane/LP gasor openingmain gasvalve
located on or near gas meter for natural gas, or using com-
pressed air.
3. Check all joints from gas meter for natural gas (see Figure 16)
or propane/LP supply tank for propane/LP gas, to equipment
shutoff valve (see Figure 17). Apply a noncorrosive leak de-
tection fluid to all joints. Bubbles forming show a leak.
4. Correct all leaks at once.
Pressure Testing Heater Gas Connections
1. Open equipment shutoff valve (see Figure 15).
2. For natural gas open main gas valve located on or near gas
meter. For propane/LP gas open propane/LPsupply tank valve.
3. Make sure control knob of heater is in the OFF position.
4. Check all joints from equipment shutoff valve to thermostat
gas valve (see Figure 16 or 17). Apply a noncorrosive leak
detection fluid to all joints. Bubbles forming show a leak.
5. Correct all leaks at once.
6. Light heater (see Operating Heater, page 13). Check all other
internal joints for leaks.
7. Turn off heater (see To Turn Off Gas to Appliance, page 14 or
16 depending on your model).
8. Replace front panel.

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13
OFF
IGNITOR
OPERATING HEATER (NON-THERMOSTAT MODELS)
For Your Safety Read Before Lighting
Lighting Instructions
OPERATING HEATER
FOR YOUR SAFETY READ
BEFORE LIGHTING
A. This appliance has a pilot which must be lighted by hand.
When lighting the pilot, follow these instructions exactly.
B. BEFORE LIGHTING smell all around the appliance area
for gas. Be sure to smell next to the floor because some gas
is heavier than air and will settle on the floor.
WHAT TO DO IFYOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electric switch; do not use any phone
in your building.
• Immediately call your gas supplier from a neighbor’s
phone. Follow the gas supplier’s instructions.
• If you cannot reach your gas supplier, call the fire de-
partment.
C. Useonlyyourhand to pushin or turnthe gas controlknob.
Never use tools. If the knob will not push in or turn by
hand, don’t try to repair it, call a qualified service techni-
cian or gas supplier. Force or attempted repair may result
in a fire or explosion.
D. Do not use this appliance if any part has been under water.
Immediately call a qualified service technician to inspect
the appliance and to replace any part of the control system
and any gas control which has been under water.
WARNING:Ifyoudonotfollow theseinstructions
exactly, a fire or explosion may result causing prop-
erty damage, personal injury or loss of life.
LIGHTING INSTRUCTIONS
Ignitor Button Control Knob
Figure18-ControlKnobInTheOFFPositionforNon-Thermostat
Models
1. STOP! Read the safety information above.
2. Make sure equipment shutoff valve is fully open.
3. Turn control knob clockwise to the OFF position.
4. Wait five minutes to clear out any gas. Then smell for gas,
including near the floor. If you smell gas, STOP! Follow
“B” in the safety information above. If you don’t smell gas,
go to the next step.
5. Turn control knob to PILOT/IGN and press in.
Note: You may be running this heater for the first time
after hooking up to gas supply. If so, you may need to press
in control knob for 30 seconds or more. This will allow air
to bleed from the gas system.
• If control knob does not pop up when released, contact a
qualified service person or gas supplier for repairs.
6. With control knob pressed in, push down and release igni-
tor button.This will light pilot. The pilot is attached to the
frontofburner. Ifneeded,keeppressingignitorbuttonuntil
pilot lights.
If pilot does not light
• turn control knob clockwise to the OFF position
• repeat steps 5 and 6
If pilot does not stay lit after several tries
• refer to Troubleshooting, pages 19 through 21
• contact a qualified service person or gas supplier for
repairs
Until repairs are made, light pilot with match. To light pi-
lot with match, see Manual Lighting Procedure, page 14.
7. Keep control knob pressed in for 30 seconds after lighting
pilot.After 30 seconds, release control knob. Note: If pilot
goes out, repeat steps 3 through 7.
Figure 19 - Pilot
NON-THERMOSTAT MODELS
Ignitor Electrode
Pilot Burner
Thermocouple

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OFF
PILOT
LOW
MED
HI
OFF
PILOT
LOW
MED
HI
OFF
PILOT
LOW
MED
HI
OFF
PILOT
LOW
MED
HI
TO TURN OFF GAS TO APPLIANCE
Shutting Off Heater
1. Turn control knob clockwise to the OFF position.
2. Turn off all electric power to the appliance if service is to
be performed.
Shutting Off Burner Only (pilot stays lit)
Turn control knob clockwise to the PILOT position.
OPERATING HEATER
Continued
1. Remove front panel (see Figure 7, page 8).
2. Followsteps1through5underLightingInstructions,page13.
3. With control knob pressed in, strike match. Hold match to
pilot until pilot lights.
4. Keep control knob pressed in for 30 seconds after lighting
pilot. After 30 seconds, release control knob. Now follow
step 8, under Lighting Instructions, page 13.
5. Replace front panel.
MANUAL LIGHTING
PROCEDURE
OPERATING HEATER (NON-THERMOSTAT MODELS)
To Select Heating Level
To Turn Off Gas To Appliance
Manual Lighting Procedure
OPERATING HEATER (THERMOSTAT MODELS)
For Your Safety Read Before Lighting
LOW
HIGH
OFF
MED
Control GWRN18 GWRN30
Knob GWRP16 GWRP26
Figure 20 - Burner Patterns for Non-Thermostat Models
TO SELECT HEATING LEVEL
Slightlypressincontrolknobandturncounterclockwise
to the LOW, MEDIUM, or HIGH positions (see Figure 20).
IMPORTANT: Release downward pressure while turning con-
trol knob. Control knob will lock at the desired position.
WARNING: When running heater, set control
knob at LOW, MEDIUM, or HIGH locked positions.
Never set control knob between locked positions.
Poorcombustionandhigherlevelsofcarbonmonox-
ide may result.
CAUTION: Do not try to adjust heating levels by
using the equipment shutoff valve.
OPERATING HEATER
FOR YOUR SAFETY READ
BEFORE LIGHTING
A. This appliance has a pilot which must be lighted by hand.
When lighting the pilot, follow these instructions exactly.
B. BEFORE LIGHTING smell all around the appliance area
for gas. Be sure to smell next to the floor because some gas
is heavier than air and will settle on the floor.
WHAT TO DO IFYOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electric switch; do not use any phone
in your building.
• Immediately call your gas supplier from a neighbor’s
phone. Follow the gas supplier’s instructions.
• If you cannot reach your gas supplier, call the fire de-
partment.
C. Useonlyyourhand to pushin or turn the gascontrolknob.
Never use tools. If the knob will not push in or turn by
hand, don’t try to repair it, call a qualified service techni-
cian or gas supplier. Force or attempted repair may result
in a fire or explosion.
D. Do not use this appliance if any part has been under water.
Immediately call a qualified service technician to inspect
the appliance and to replace any part of the control system
and any gas control which has been under water.
WARNING:Ifyoudonotfollow theseinstructions
exactly, a fire or explosion may result causing prop-
erty damage, personal injury or loss of life.
THERMOSTAT MODELS

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15
OPERATING HEATER (THERMOSTAT MODELS)
Lighting Instructions
OPERATING HEATER
Continued
1. STOP! Read the safety information, column 2 page 14.
2. Make sure equipment shutoff valve is fully open.
3. Turnthermostatcontrolknob clockwise
Clockwise
to theOFF
position (see Figure 21).
4. Wait five minutes to clear out any gas. Then smell for gas,
including near the floor. If you smell gas, STOP! Follow
“B” in the safety information, column 2 page 14. If you
don’t smell gas, go to the next step.
5. Turn thermostat control knob counterclockwise
C-clockwise
to the PILOT position. Press in thermostat control knob
for 5 seconds (see Figure 21).
Note: You may be running this heater for the first time
after hooking up to gas supply. If so, you may need to press
in thermostat control knob for 30 seconds or more. This
will allow air to bleed from the gas system.
• If thermostat control knob does not pop up when released,
contactaqualifiedservicepersonor gassupplierforrepairs.
6. Keepthermostatcontrolknobpressedinwhilepushingdown
and releasing the ignitor button.This will light pilot. If nec-
essary, continue to press ignitor button until pilot lights.
If pilot does not light
• turn thermostat control knob clockwise
Clockwise
to the
OFF position
• repeat steps 5 and 6
If pilot does not stay lit after several tries
• refer to Troubleshooting, pages 19 through 21
• contact a qualified service person or gas supplier
Until repairs are made, light pilot with match. To light
pilotwith match,seeManualLightingProcedure,page16.
7. Keep thermostat control knob pressed in for 30 seconds
after lighting pilot.After 30 seconds, release control knob.
Note: If pilotgoesout,repeatsteps 3through7.This heater
hasa safety interlocksystem.Wait one minute before light-
ing pilot again.
8. Turn thermostat control knob counterclockwise
C-clockwise
to the desired heating level.The main burner should light.
Set control knob to any heat level between HI and LOW
(see Figure 23).
LIGHTING
INSTRUCTIONS
CAUTION: Do not try to adjust heating levels by
using the equipment shutoff valve.
IGNITOR
PILOT
LO
OFF
HI
Figure 21 - Control Knob In The OFF Position
Control
Knob
Ignitor
Button
Figure 22 - Pilot
Figure 23 - Burner Patterns
OFF
HI
LO
PILOT
OFF
HI
LO
PILOT
Control Knob GWRP16T
GWRN18T GWRP26T
GWRN30T
Ignitor Electrode
Pilot Burner
Thermocouple

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GRH/OV 008BAD PILOT/LP
GRH/OV 007GOOD PILOT/LP
INSPECTING HEATER
Thermocouple Pilot
Burner Pilot
Burner
Thermocouple
Blue
Flame
Yellow Flame
OPERATING HEATER (THERMOSTAT MODELS)
To Turn Off Gas To Appliance
Thermostat Operation
Manual Lighting Procedure
INSPECTING HEATER
Pilot Flame Pattern
Burner Flame Pattern
OPERATING HEATER
Continued
1. Followsteps1through5underLightingInstructions,page15.
2. With thermostat control knob pressed in, strike match.
Hold match to pilot until pilot lights.
3. Keep thermostat control knob pressed in for 30 seconds
after lighting pilot.After 30 seconds, release control knob.
Follow step 8 under Lighting Instructions, page 15.
Shutting Off Heater
1. Turn thermostatcontrolknobclockwise
Clockwise
to theOFF
position.
2. Turn off all electric power to the appliance if service is to
be performed.
Shutting Off Burner Only (pilot stays lit)
Turn thermostat control knob clockwise
Clockwise
to the PILOT
position.
THERMOSTAT
OPERATION
The thermostatic control used on these models differs from
standardthermostats.Standardthermostatssimply turnon and
off the burner. The thermostat used on this heater senses the
room temperature. At times the room may exceed the set tem-
perature.Ifso,theburnerwillshutoff.Theburnerwillcycleback
onwhenroomtemperaturedropsbelowthesettemperature.The
controlknobcanbesettoany2comfortlevelbetweenHIandLO.
All plaques will turn off and on.
Note: Thethermostatsensingbulbmeasuresthetemperatureof
airneartheheatercabinet.Thismaynotalwaysagreewithroom
temperature (depending on housing construction, installation
location, room size, open air temperatures, etc.) Frequent use of
your heater will let you determine your own comfort levels.
TO TURN OFF GAS
TO APPLIANCE
MANUAL LIGHTING
PROCEDURE
Check pilot flame pattern and burner flame pattern often.
PILOT FLAME PATTERN
Figure 24 shows a correct pilot flame pattern. Figure 25 shows an
incorrect pilot flame pattern. The incorrect pilot flame is not
touching the thermocouple. This will cause the thermocouple to
cool. When the thermocouple cools, the heater will shut down.
If pilot flame pattern is incorrect, as shown in Figure 25
• turn heater off (seeTo Turn Off Gas to Appliance, page 14 [non-
thermostat models] or page 16 [thermostat models])
• see Troubleshooting, pages 19 through 21
Note: The pilot flame on natural gas units will have a slight curve,
but flame should be blue and have no yellow or orange color.
Figure 24 - Correct Pilot Flame
Pattern Figure25-IncorrectPilotFlame
Pattern
BURNER FLAME PATTERN
Figure26 shows a correct burner flame pattern.Figure 27shows an
incorrect burner flame pattern.
If burner flame pattern is incorrect, as shown in Figure 27
• turn heater off (seeTo Turn Off Gas to Appliance, page 14 [non-
thermostat models] or page 16 [thermostat models]))
• see Troubleshooting, pages 19 through 21
Figure 26 - Correct Burner
Flame Pattern
Bad Burner Pattern-Plaque GRH/OV 019
Figure 27 - Incorrect Burner
Flame Pattern

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17
CLEANING AND
MAINTENANCE
ODS/PILOT AND BURNER
• Use a vacuum cleaner, pressurized air, or small, soft bristled
brush to clean.
CLEANING BURNER PILOT AIR INLET
Theprimaryairinletholesallowtheproperamountofairtomixwith
the gas. This provides a clean burning flame. Keep these holes clear
of dust, dirt, and lint. Clean these air inlet holes prior to each heating
season. Blocked air holes will create soot. We recommend that you
clean the unit every three months during operation and have heater
inspected yearly by a qualified service person.
We also recommend that you keep the burner tube and pilot
assembly clean and free of dust and dirt. To clean these parts we
recommendusingcompressedairnogreaterthan30PSI.Yourlocal
computer store, hardware store, or home center may carry com-
pressed air in a can. You can use a vacuum cleaner in the blow
position. If using compressed air in a can, please follow the direc-
tionsonthe can.Ifyoudon't followdirectionsonthe can,youcould
damage the pilot assembly.
1. Shut off the unit, including the pilot.Allow the unit to cool for
at least thirty minutes.
2. Inspect burner, pilot for dust and dirt.
3. Blow air through the ports/slots and holes in the burner.
4. Never insert objects into the pilot tube.
Clean the pilot assembly also. A yellow tip on the pilot flame
indicates dust and dirt in the pilot assembly. There is a small pilot
air inlet about two inches from where the pilot flame comes out of
thepilotassembly(seeFigure28).Withtheunitoff,lightlyblowair
through the air inlet. You may blow through a drinking straw if
compressed air is not available.
WARNING: Turn off heater and let cool before
cleaning.
CAUTION: You must keep control areas, burner,
and circulating air passageways of heater clean. In-
spect these areas of heater before each use. Have
heater inspected yearly by a qualified service person.
Heatermayneedmorefrequentcleaningduetoexces-
sivelintfromcarpeting,beddingmaterial,pethair,etc.
CLEANING AND MAINTENANCE
ODS/Pilot and Burner
Cleaning Burner Pilot Air Inlet
Cabinet
CABINET
Air Passageways
• Use a vacuum cleaner or pressurized air to clean.
Exterior
• Use a soft cloth dampened with a mild soap and water mixture.
Wipe the cabinet to remove dust.
Figure 28 - Pilot Air Inlet
Pilot Assembly
Pilot Air Inlet

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SPECIFICATIONS
SPECIFICATIONS
GWRN18 GWRN30
GWRN18T GWRN30T
Btu (Variable) 6,600/12,000/18,000 6,600/18,000/30,000
Type Gas Natural Only Natural Only
Ignition Piezo Piezo
Pressure Regulator Setting 6" W.C. 6" W.C.
Inlet Gas Pressure* (in. of water)
Maximum 10.5" 10.5"
Minimum 7" 7"
Dimensions, Inches (H x W x D)
Heater 24 1/4x 18 1/4x 7 24 1/4x 25 3/4x 7
Carton 26 3/8x 20 7/8x 10 26 3/8x 28 1/8x 10
Weight (pounds)
Heater 20 28
Shipping 25 33
Note :Dimensions listed are outer most points
on the heater (includes control knobs and grill).
* For purposes of input adjustment.
GWRP16 GWRP26
GWRP16T GWRP26T
Btu (Variable) 6,000/11,000/16,000 6,000/16,000/26,000
Type Gas Propane/LP Only Propane/LP Only
Ignition Piezo Piezo
Pressure Regulator Setting 8" W.C. 8" W.C.
Inlet Gas Pressure* (in. of water)
Maximum 14" 14"
Minimum 11" 11"
Dimensions, Inches (H x W x D)
Heater 24 1/4x 18 1/4x 7 24 1/4x 25 3/4x 7
Carton 26 3/8x 20 7/8x 10 26 3/8x 28 1/8x 10
Weight (pounds)
Heater 20 28
Shipping 25 33
Note :Dimensions listed are outer most points
on the heater (includes control knobs and grill).
* For purposes of input adjustment.

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19
TROUBLESHOOTING
TROUBLESHOOTING WARNING: Turn off and un-
plug heater and let cool before
servicing. Only a qualified ser-
vice person should service and
repair heater.
CAUTION: Never use a wire,
needle, or similar object to clean
ODS/pilot.ThiscandamageODS/
pilot unit.
POSSIBLE CAUSE
1. Ignitor electrode positioned wrong
2. Ignitor electrode broken
3. Ignitor electrode not connected to igni-
tor cable
4. Ignitor cable pinched or wet
5. Broken ignitor cable
6. Bad piezo ignitor
7. Piezo ignitor nut is loose
1. Gas supply turned off or equipment
shutoff valve closed
2. Control knob not fully pressed in while
pressing ignitor button (non-thermostat
models only)
Thermostat control knob not fully
pressed in while pressing ignitor button
(thermostat models only)
3. Air in gas lines when installed
4. Depleted gas supply (propane/LP gas)
5. ODS/pilot is clogged
6. Gas regulator setting is not correct
7. Thermostat control knob is not in pilot
position (thermostat models only)
REMEDY
1. Replace pilot assembly
2. Replace pilot assembly
3. Reconnect ignitor cable
4. Free ignitor cable if pinched by any
metal or tubing. Keep ignitor cable dry
5. Replace ignitor cable
6. Replace piezo
7. Tighten nut holding piezo ignitor. Nut
is located inside heater cabinet at top
1. Turn on gas supply or open equipment
shutoff valve
2. Turnto PILOT/IGNposition. Fully press
in control knob while pressing ignitor
button (non-thermostat models only)
Fully press in thermostat control knob
while pressing ignitor button (thermo-
stat models only)
3. Continue holdingdown controlknob. Re-
peatignitingoperationuntilairisremoved
4. Contact local propane/LP gas company
5. Clean ODS/pilot (see Cleaning and
Maintenance, page 17) or replace ODS/
pilot assembly
6. Replace gas regulator
7. Turn thermostat control knob to pilot
position
OBSERVED PROBLEM
Whenignitorbuttonispressedin,thereisno
spark at ODS/pilot
When ignitor button is pressed in, there is a
spark at ODS/Pilot but no ignition
Note: For additional help, visit DESA
International’stechnicalservicewebsite
at www.desatech.com.
Note: Alltroubleshootingitemsarelistedin
order of operation.

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TROUBLESHOOTING
OBSERVED PROBLEM
ODS/pilot lights but flame goes out when
control knob is released
Burner(s)does not lightafter ODS/pilot islit
Delayed ignition of burner(s)
Burner backfiring during combustion
Burner plaque(s) does not glow
Slightsmoke or odorduringinitial operation
Heater produces a clicking/ticking noise
just after burner is lit or shut off
REMEDY
1. Press in control knob fully
2. After ODS/pilot lights, keep control
knob pressed in 30 seconds
3. Fully open equipment shutoff valve
4. Hand tighten until snug, then tighten 1/4
turn more
5. A) Contact local natural or propane/LP
gas company
B) Clean ODS/pilot (see Cleaning and
Maintenance, page 17) or replace ODS/
pilot assembly
6. Replace pilot assembly
7. Replace control valve
8. Waitone minutefor safety interlock sys-
tem to reset. Repeat ignition operation
1. Clean burner orifice(s) (see Cleaning
and Maintenance, page 17) or replace
burner orifice(s)
2. Contact local natural or propane/LP gas
company
1. Contact local natural or propane/LP gas
company
2. Clean burner orifice(s) (see Cleaning
and Maintenance, page 17) or replace
burner orifice(s)
1. Clean burner orifice(s) (see Cleaning
and Maintenance, page 17) or replace
burner orifice(s)
2. Replace burner
3. Replace gas regulator
1. Replace burner
2. Contact local natural or propane/LP gas
company
3. Turn control knob until it locks at de-
sired setting
1. Problem will stop after a few hours of
operation
1. This is common with most heaters. If
noise is excessive, contact qualified ser-
vice person
POSSIBLE CAUSE
1. Control knob not fully pressed in
2. Control knobnot pressedin longenough
3. Equipment shutoff valve not fully open
4. Thermocouple connection loose at con-
trol valve
5. Pilot flame not touching thermocouple,
which allows thermocouple to cool,
causing pilot flame to go out. This prob-
lem could be caused by one or both of
the following:
A) Low gas pressure
B) Dirty or partially clogged ODS/pilot
6. Thermocouple damaged
7. Control valve damaged
8. Safety interlock system has been trig-
gered (thermostat models only)
1. Burner orifice(s) is clogged
2. Inlet gas pressure is too low
1. Manifold pressure is too low
2. Burner orifice(s) is clogged
1. Burner orifice(s) is clogged or damaged
2. Burner damaged
3. Gas regulator defective
1. Plaque damaged
2. Inlet gas pressure is too low
3. Control knob set between locked posi-
tions
1. Residues from manufacturing processes
1. Metal expanding while heating or con-
tracting while cooling
TROUBLESHOOTING
Continued