Comfort Glow CBN20, CBP20, SBN20, SBP20, CB Original instructions

UNVENTED (VENT-FREE)
BLUE FLAME GAS HEATER
SAFETY INFORMATION AND
INSTALLATION MANUAL
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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:Improperinstallation,
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:Thisisanunvented
gas-firedheater.Itusesair(oxy-
gen) from the room in which it
is installed. Provisions for ad-
equate combustion and venti-
lation air must be provided.
RefertoAirforCombustionand
Ventilationsectiononpage4of
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.
CBN20, CBP20
CBN20T, CBP20T
CBN30T, CBP30T
CBT20NT, CBT20PT
CBT30NT, CBT30PT
CBN20TK, CBP20TK

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Due to high temperatures, the appliance should be
located out of traffic and away from furniture and
draperies.
Do not place clothing or other flammable material on
orneartheappliance.Never place anyobjectsonthe
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.
Keeptheapplianceareaclearandfree from combus-
tible materials, gasoline and other flammable vapors
and liquids.
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 (propane/LP mod-
els only).
WARNING: Do not use any accessory not ap-
proved for use with this heater.
Carbon Monoxide Poisoning: Early signs of carbon monoxide
poisoningresemblethe flu,withheadaches, 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.
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............................................................. 14
CLEANING AND MAINTENANCE ............................................ 15
SPECIFICATIONS .................................................................... 16
SERVICE HINTS....................................................................... 16
TECHNICAL SERVICE ............................................................. 16
SERVICE PUBLICATIONS ....................................................... 16
TROUBLESHOOTING .............................................................. 17
ILLUSTRATED PARTS BREAKDOWNAND PARTS LIST ....... 20
REPLACEMENT PARTS .......................................................... 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
3. 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
4. This heater shall not be installed in a bedroom or bathroom.
5. 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.
6. Keep all air openings in front and bottom of heater clear and free
of debris. This will insure enough air for proper combustion.
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 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 (propane/LP models only).
13. Provide adequate clearances around air openings.
SAFETY INFORMATION PRODUCT IDENTIFICATION
LOCAL CODES
Installanduseheaterwithcare. Followalllocalcodes.Intheabsence
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. Removeallprotective packagingapplied toheaterforshipment.
3. Check heater for any shipping damage. If heater is damaged,
promptly return to dealer where you bought heater.
Control Knob & Ignitor Button
(not seen from this view)
Heater
Cabinet
Front
Panel
Glass
Panel
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.
IGNITION SYSTEM
This heater has either a piezo ignitor or electronic ignitor to light
heater fuel supply.
THERMOSTATIC HEAT CONTROL
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,increasedinsulation, andnew constructionmethods help
reduce heat loss in homes. Home owners weather strip and caulk
aroundwindowsand doorsto keepthe coldairout andthe warmair
in. During heating months, home owners want their homes as
airtight 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,between wall-ceiling joints,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.
Ifyourhomedoesnotmeetallof the three criteria above,
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
furnishedwith doors,areconsideredapart ofthe unconfinedspace.
* 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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5
AIR FOR COMBUSTION AND
VENTILATION
Continued
DETERMINING FRESH-AIR FLOW FOR
HEATER LOCATION
Determining if You Have a Confined or
Unconfined Space
Usethisworksheetto determine if youhaveaconfined or unconfined 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)
Ifadditionalventilationtoadjoiningroom is supplied with grillsoropen-
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)
The space in the above example is a confined space because the actual Btu/Hr
used is more than the maximum Btu/Hr the space can support. You must
provide additional fresh air. Your options are as follows:
A. Rework worksheet, adding the space of an adjoining room. If the
extra space provides an unconfined space, remove door to adjoining
roomor add ventilationgrillsbetween rooms.See Ventilation Air From
Inside Building, page 6.
B. Vent room directly to the outdoors. See Ventilation Air From Out-
doors, page 6.
C. Installa lowerBtu/Hr heater, if lowerBtu/Hr size makesroomunconfined.
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 airby usingventilationgrillsor ducts.Youmust
provide two permanent openings: one within 12" of the ceiling and
one within 12" of the floor. Connect these items directly to the
outdoorsorspacesopento theoutdoors. 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
Or
Remove
Door into
Adjoining
Room,
Option 3
Ventilation Grills
Into Adjoining Room,
Option 2
12"
12"
Ventilation
Grills
into Adjoining
Room,
Option 1
Outlet
Air Ventilated
Attic
Outlet
Air
Inlet
Air
Inlet Air Ventilated
Crawl Space
To
Crawl
Space
To Attic

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7
INSTALLATION
WARNING: A qualified service person must in-
stall heater. Follow all local codes.
CHECK GAS TYPE
Useonly thecorrect typeof gas(naturalorpropane/LP).Ifyourgas
supply is not the correct gas type, do not install heater. Call dealer
where you bought heater for proper type heater.
INSTALLATION ITEMS
Beforeinstalling heater,makesureyouhave theitemslistedbelow.
• 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
• 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.
These currents move heat to wall surfaces next to
heater. Installing heater next to vinyl or cloth wall
coveringsoroperatingheaterwhereimpurities(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
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 the floor, away from a wall. A wall
mountingbracketandfloorbase standareincluded withthisheater.
Determine which method is best for your application.
Figure4-MountingClearancesAsViewedFromFrontofHeater
INSTALLATION
Check Gas Type
Installation Items
Locating Heater
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
6"
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-freeheaters addmoistureto 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.

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INSTALLATION
Thermostat Sensing Bulb
Installing Heater To Wall
WARNING:Maintainminimumclearancesshown
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.
INSTALLATION
Continued
THERMOSTAT SENSING BULB
Thethermostatsensing bulbhasbeenplaced insidethe heaterfor
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.
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.
Figure 5 - Attaching Thermostat Sensing Bulb
INSTALLING HEATER TO WALL
Mounting Bracket
Locate mounting bracket in heater carton. Remove mounting bracket
from heater carton.
Figure 7 - Removing Front Panel Of Heater
Removing Front Panel Of Heater
1. Removethefourpaintedscrews, twoon eachside offront panel.
2. Pull bottom of front panel forward, then out.
3. Remove any remaining packaging materials.
Figure 6 - Mounting Bracket
Clamp
Thermostat Sensing Bulb

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9
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.
Figure 8 - Mounting Bracket Clearances
18
3
/ 4 "
Min.
12"
Min. 14"
Adjoining Wall
Only Insert Mounting
Screws Through Last
Hole On Each End
Floor
14"
18
3
/ 4 "
Min.
8"
Min.
Adjoining Wall
Only Insert Mounting
Screws Through Last
Hole On Each End
Floor
Attaching Mounting Bracket To Wall
Note: Wall anchors, mounting screws, and spacers are in hardware
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
Figure 11 - Mounting Heater Onto Mounting Bracket
Mounting Bracket
(attached to wall)
Horizontal Slots
Stand-Out Tab
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. Insert wall anchor (wings first) into hole. Tap anchor flush
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. Tightenscrews untilmounting bracketisfirmlyfastenedto 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.
30,000 Btu/hr Models
20,000 Btu/hr Models

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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.)
Mounting Heater To Floor
MOUNTING HEATER TO FLOOR
Mounting Base Feet to Heater
1. Lay heater cabinet on its back on a table with the heater bot-
tom overhanging the table edge.
2. Align holes in base foot with mounting holes on bottom of
cabinet (see Figure 13).
3. Secure base foot to heater using sheet metal screws.
4. Repeat for other side.
Mounting Base Feet to Floor (Where required by
local code)
1. Removefront cover(seeRemovingFrontPanelof Heater, page8).
2. Position heater with base feet in desired location. Mark holes
for drilling. Remove heater with base.
3. For carpeted floors, make a small cut with a sharp knife at
marked locations prior to drilling. If mounting base to a wood
floor, drill 1/8 inch diameter hole, 3/4 inch deep. (Do not use
anchors in wood floors).
If mounting base to a concrete floor, drill with 1/4 inch diam-
eter concrete drill bit, 13/8inches into floor. Insert anchors com-
pletely into holes.
4. Reposition heaterwith basefeetover holes.Securebase tofloor
with wood screws. See Figure 13.
Figure 13 - Installing Base Feet
Wood
Screw
Sheet Metal Screw
Base Foot
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
Forpropane/LPgas,theinstallermustsupply anexternal regulator.
Theexternalregulatorwillreduceincominggaspressure.Youmust
reduceincominggas pressuretobetween11 and14inchesofwater.
Ifyoudonotreduceincominggaspressure,heaterregulatordamage
could occur. Install the external regulator with the vent pointing
downasshowninFigure14.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.
Typical Inlet Pipe Diameters
20,000 Btu/Hr Models - 3/8" or greater
30,000 Btu/Hr Models - 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 15).
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.
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.
Install sediment trap in supply line as shown in Figure 15. Locate
sedimenttrapwhere itis withinreachforcleaning. 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:Usepipejointsealant that is resistant
to liquid petroleum (LP) gas.
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
connectingheatertogasline.Gaslinepressuremustbenogreaterthan
14 inches of water. If gas line pressure is higher, heater regulator
damage could occur.
WARNING:Fornaturalgas,neverconnectheater
to private (non-utility) gas wells. This gas is com-
monly known as wellhead gas.
CONNECTING TO GAS SUPPLY
Figure 14 - External Regulator With Vent Pointing Down
External
Regulator
Propane/LP
Supply
Tank
Vent
Pointing
Down
* 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 15 - Gas Connection
Pressure
Regulator
Tee Joint
Reducer
Bushing to
1/8" NPT
1/8" NPT
Plug Tap
Test
Gauge
Connection*
Tee
Joint
Pipe
Nipple
Cap
3/8" NPT
Pipe Nipple Heater
Cabinet
Sediment
Trap
Equipment
Shutoff Valve *
3"
Minimum
Natural Gas
From Gas Meter
(5" W.C. to 10.5"
W.C. Pressure)
Propane/LP
From External
Regulator
(11" W.C. to 14"
W.C. Pressure)
Ground Joint Union
Note: Burner
bracket not
shown for
clarity

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INSTALLATION
Continued
INSTALLATION
Checking Gas Connections
WARNING: Test all gas piping and connections,
internal and external to unit, for leaks after installing
or servicing. Correct all leaks at once.
WARNING:Never useanopenflame tocheckfor
a leak. Apply a noncorrosive leak detection fluid to
all joints. Bubbles forming show a leak. Correct all
leaks at once.
CAUTION: For propane/LP gas, make sure exter-
nalregulatorhas beeninstalledbetweenpropane/LP
supply and heater. See guidelines under Connecting
to Gas Supply , page 11.
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
supplytankvalve forpropane/LP gasoropening maingas valve
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.
Test Pressures Equal To or Less Than 1/2 PSIG (3.5 kPa)
1. Close equipment shutoff valve (see Figure 16).
2. Pressurize supply piping system by either opening propane/LP
supplytankvalve forpropane/LP gasoropening maingas valve
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 17)
or propane/LP supply tank for propane/LP gas, to equipment
shutoff valve (see Figure 18). Apply a noncorrosive leak de-
tection fluid to all joints. Bubbles forming show a leak.
4. Correct all leaks at once.
CHECKING GAS CONNECTIONS
Figure 18 - Checking Gas Joints for Propane/LP Gas
Figure 16 - Equipment Shutoff Valve
Equipment
Shutoff
Valve
Propane/LP
Supply
Tank
Thermostat
Gas Valve
O
N
POSI
T
O
PO
S
Open
Closed
Equipment
Shutoff
Valve
Figure 17 - Checking Gas Joints for Natural Gas
Equipment
Shutoff
Valve
Gas
Meter
Thermostat
Gas Valve
Pressure Testing Heater Gas Connections
1. Open equipment shutoff valve (see Figure 16).
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 17 or 18). 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).
8. Replace front panel.

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13
OPERATING HEATER
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 push in orturnthegascontrolknob.
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:Ifyoudonotfollowtheseinstructions
exactly, a fire or explosion may result causing prop-
erty damage, personal injury or loss of life.
LIGHTING
INSTRUCTIONS
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 (5) minutes to clear out any gas. Then smell for
gas, including near the floor. If you smell gas, STOP! Fol-
low “B” in the safety information above. If you don’t smell
gas, go to the next step.
5. Turncontrolknobcounterclockwise tothePILOT
position. Press in control knob for five (5) seconds (see Fig-
ure 19).
Figure 19 - Control Knob In The OFF Position (Piezo Ignitor
Shown)
PILOT
LO
OFF
HI
IGNITOR
Ignitor Button Control Knob
CAUTION: Do not try to adjust heating levels by
using the equipment shutoff valve.
Figure 20 - Pilot (actual pilot may vary)
Ignitor Electrode
Pilot Burner
Thermocouple
Note: You may be running this heater for the first time
after hooking up to gas supply. If so, the control knob may
need to be pressed in for 30 seconds or more. This will al-
low 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 (see Figure 19). This will light pilot. The pilot is
attachedto thefrontofburner.Thepilot canbeseenthrough
the glass panel. If needed, keep pressing ignitor button until
pilot lights.
Note: If pilot does not stay lit, refer to Troubleshooting,
pages 17 through 19. Also contact a qualified service per-
sonorgas supplierforrepairs.Until repairsaremade,light
pilot with match. To light pilot 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.
• If control knob does not pop up when released, contact a
qualified service person or gas supplier for repairs.
Note: If pilot goes out, repeat steps 3 through 7. This
heater has a safety interlock system.Wait one (1) minute
before lighting pilot again.
8. Turn control knob counterclockwise to desired
heating level. The main burner should light. Set control
knob to any heat level between HI and LO.

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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.
THERMOSTAT CONTROL
OPERATION
The thermostatic control used on these models differs from
standard thermostats. Standard thermostats simply turn on
and off the burner. The thermostat used on this heater senses
the room temperature. The thermostat adjusts the amount of
gas flow to the burner. This increases or decreases the burner
flameheight.Attimestheroommayexceedthesettemperature.
If so, the burner will shut off. The burner will cycle back on
when room temperature drops below the set temperature. The
control knob can be set to any heat level between HI and LO.
SelectingtheHI settingwillcausethe burnertoremainfully on
without modulating down in most cases.
Note: The thermostat sensing bulb measures the temperature
of air near the heater cabinet. This may not always agree with
room temperature (depending on housing construction, instal-
lation location, room size, open air temperatures, etc.). Fre-
quent use of your heater will let you determine your own
comfort levels.
MANUAL LIGHTING
PROCEDURE
OPERATING HEATER
To Turn Off Gas To Appliance
Thermostat Control
Manual Lighting Procedure
INSPECTING HEATER
Pilot Flame Pattern
INSPECTING HEATER
Check pilot flame pattern and burner flame pattern often.
PILOT FLAME PATTERN
Figure 21 shows a correct pilot flame pattern. Figure 22 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 22
• turn heater off (see To Turn Off Gas to Appliance)
• see Troubleshooting, pages 17 through 19
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 22 - Incorrect Pilot Flame Pattern
Figure 21 - Correct Pilot Flame Pattern
Thermocouple
Pilot Burner
Pilot Burner
Thermocouple
Blue Flame
Yellow Flame

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15
INSPECTING HEATER
Burner Flame Heater
CLEANING AND MAINTENANCE
ODS/Pilot and Burner
Cleaning Burner Pilot Air Inlet
Cabinet
NOTICE: Do not mistake orange flames with yellow
tipping. Dirt or other fine particles enter the heater
and burn causing brief patches of orange flame.
WARNING: If yellow tipping occurs, your heater
could produce increased levels of carbon monoxide.
BURNER FLAME PATTERN
Figure 23 shows a correct burner flame pattern. Figure 24 shows an
incorrect burner flame pattern. The incorrect burner flame pattern
shows yellow tipping of the flame. It also shows the flame higher
than 1/2 the glass panel height.
If burner flame pattern is incorrect, as shown in Figure 24
• turn heater off (see To Turn Off Gas To Appliance, page 14)
• see Troubleshooting, pages 17 through 19
1/2
G
Figure 23 - Correct Burner Flame Pattern
Yellow Tipping
1/2
G
Figure 24 - Incorrect Burner Flame Pattern
1/2Glass
Height
1/2Glass
Height
Blue
Flame
INSPECTING HEATER
Continued
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
Theprimaryairinlet holesallowthe properamountof airtomix with
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-
tionsonthecan.Ifyoudon'tfollowdirectionsonthecan, 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(seeFigure25).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.
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 25 - Pilot Inlet Air (Propane/LP Pilot Shown)
Pilot Assembly
Pilot Air Inlet
WARNING: Failure to keep the primary air
opening(s) of the burner(s) clean may result in soot-
ing and property damage.

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16
TECHNICAL SERVICE
You may have further questions about installation, operation, or
troubleshooting. If so, contact DESA Heating Products’ Technical
Service Department at 1-866-672-6040. When calling please have
your model and serial numbers of your heater ready.
You can also visit DESA Heating Products’ technical service web
site at www.desatech.com.
SERVICE HINTS
When Gas Pressure Is Too Low
• pilot will not stay lit
• burner will have delayed ignition
• heater will not produce specified heat
• propane/LP gas supply may be low
You may feel your gas pressure is too low. If so, contact your local
natural or propane/LP gas supplier. SERVICE PUBLICATIONS
You can purchase a service manual from the address listed on the
back page of this manual. Send a check for $5.00 payable to DESA
Heating Products.
SPECIFICATIONS
CBN20/CBN20T CBN30T CBT20NT CBT30NT
Btu (Variable) 10,000/20,000 15,000/30,000 10,000/20,000 15,000/30,000
Type Gas Natural Only Natural Only Natural Only Natural Only
Ignition Piezo Piezo Electronic Electronic
Pressure Regulator Setting 3" W.C. 3" W.C. 3" W.C. 3" W.C.
Inlet Gas Pressure (in. of water)
Maximum 10.5" 10.5" 10.5" 10.5"
Minimum 4" 4" 4" 4"
Dimensions, Inches (H x W x D)
Heater (Includes knobs & grill) 26.25 x 18.25 x 7 26.25 x 25.75 x 7 26.25 x 18.25 x 7 26.25 x 25.75 x 7
Carton 28.25 x 21.25 x 9 28.25 x 29 x 9 28.25 x 21.25 x 9 28.25 x 29 x 9
Weight (pounds)
Heater 20 28 20 28
Shipping 25 33 25 33
CBP20/CBP20T CBP30T CBT20PT CBT30PT
Btu (Variable) 10,000/20,000 15,000/30,000 10,000/20,000 15,000/30,000
Type Gas Propane/LP Only Propane/LP Only Propane/LP Only Propane/LP Only
Ignition Piezo Piezo Electronic Electronic
Pressure Regulator Setting 8" W.C. 8" W.C. 8" W.C. 8" W.C.
Inlet Gas Pressure (in. of water)
Maximum 14" 14" 14" 14"
Minimum 11" 11" 11" 11"
Dimensions, Inches (H x W x D)
Heater (Includes knobs & grill) 26.25 x 18.25 x 7 26.25 x 25.75 x 7 26.25 x 18.25 x 7 26.25 x 25.75 x 7
Carton 28.25 x 21.25 x 9 28.25 x 29 x 9 28.25 x 21.25 x 9 28.25 x 29 x 9
Weight (pounds)
Heater 20 28 20 28
Shipping 25 33 25 33
SPECIFICATIONS
SERVICE HINTS
TECHNICAL SERVICE
SERVICE PUBLICATIONS

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17
TROUBLESHOOTING
TROUBLESHOOTING
WARNING:Turnoffandunplug
heater and let cool before servic-
ing.Onlyaqualifiedserviceperson
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 ignitor
7. Battery not installed, battery power low,
or battery not installed correctly (elec-
tronic ignition models only)
1. Gas supply turned off or equipment
shutoff valve closed
2. Control knob not in PILOT position
3. Control knob not pressed in while in
PILOT position
4. Air in gas lines when installed
5. Depletedgassupply(propane/LPgasonly)
6. ODS/pilot is clogged
7. Gas regulator setting is not correct
1. Control knob not fully pressed in
2. Control knobnot pressed inlongenough
3. Safety interlocksystemhas beentriggered
4. Equipment shutoff valve not fully open
5. Thermocouple connection loose at con-
trol valve
6. 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
7. Thermocouple damaged
8. Control valve damaged
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 ignitor
7. Install new alkaline battery in elec-
tronic ignitor.Verify battery is installed
correctly
1. Turn on gas supply or open equipment
shutoff valve
2. Turn control knob to PILOT position
3. Press in control knob while in PILOT
position
4. Continue holdingdowncontrol knob.Re-
peatignitingoperationuntil airisremoved
5. Contact local propane/LP gas company
6. Clean ODS/pilot (see Cleaning and
Maintenance, page 15) or replace ODS/
pilot assembly
7. Replace gas regulator
1. Press in control knob fully
2. After ODS/pilot lights, keep control
knob pressed in 30 seconds
3. Wait oneminute for safetyinterlocksys-
tem to reset. Repeat ignition operation
4. Fully open equipment shutoff valve
5. Hand tighten until snug, then tighten 1/4
turn more
6. A) Contact local natural or propane/LP
gas company
B) Clean ODS/pilot (see Cleaning and
Maintenance, page 15) or replace ODS/
pilot assembly
7. Replace pilot assembly
8. Replace control valve
OBSERVED PROBLEM
When ignitor button is pressed, there is no
spark at ODS/pilot
When ignitor button is pressed, there is
spark at ODS/pilot but no ignition
ODS/pilot lights but flame goes out when
control knob is released
Note: For additional help, visit DESA
HeatingProducts’technicalserviceweb
site at www.desatech.com.
Note: Alltroubleshootingitemsarelistedin
order of operation.

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OBSERVED PROBLEM
Burner does not light after ODS/pilot is lit
Delayed ignition of burner
Burner backfiring during combustion
Yellow flame during burner combustion
Slightsmoke orodor duringinitialoperation
Heater produces a whistling noise when
burner is lit
Whitepowderresidueformingwithinburner
box or on adjacent walls or furniture
REMEDY
1. Clean burner (see Cleaning and Mainte-
nance, page 15) or replace burner orifice
2. Contact local natural or propane/LP gas
company
1. Contact local natural or propane/LP gas
company
2. Clean burner (see Cleaning and Mainte-
nance, page 15) or replace burner orifice
1. Clean burner (see Cleaning and Mainte-
nance, page 15) or replace burner orifice
2. Replace burner
3. Replace gas regulator
1. Check burner for dirt and debris. If
found, clean burner (see Cleaning and
Maintenance, page 15)
2. Replace gas regulator
3. Clean burner (see Cleaning and Main-
tenance, page 15)
1. Problem will stop after a few hours of
operation
1. Turn control knob to LO position and
let warm up for a minute
2. Operate burner until air is removed from
line. Have gas line checked by local
natural or propane/LP gas company
3. Observe minimum installation clear-
ances (see Figure 4, page 7)
4. Clean burner (see Cleaning and Mainte-
nance, page 15) or replace burner orifice
1. Turn heater off when using furniture
polish, wax, carpet cleaners, or similar
products
POSSIBLE CAUSE
1. Burner orifice is clogged
2. Inlet gas pressure is too low
1. Manifold pressure is too low
2. Burner orifice is clogged
1. Burner orifice is clogged or damaged
2. Burner damaged
3. Gas regulator defective
1. Not enough air
2. Gas regulator defective
3. Clogged or dirty burner
1. Residues from manufacturing processes
1. Turning control knob to HI position
when burner is cold
2. Air in gas line
3. Air passageways on heater blocked
4. Dirty or partially clogged burner orifice
1. When heated,vaporsfrom furniturepol-
ish, wax, carpet cleaner, etc., may turn
into white powder residue
TROUBLESHOOTING
Continued
TROUBLESHOOTING

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19
TROUBLESHOOTING
WARNING: 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.
•Immediatelycallyourgassupplierfromaneighbor’sphone.Followthe
gas supplier’s instructions.
•If you cannot reach your gas supplier, call the fire department.
TROUBLESHOOTING
Continued
POSSIBLE CAUSE
1. Metal expanding while heating or con-
tracting while cooling
1. Heater burning vapors from paint, hair
spray, glues, etc. (see IMPORTANT
statement above)
2. Low fuel supply (propane/LP gas only)
3. Gas leak. SeeWarning statement at
top of page
1. Not enough fresh air is available
2. Low line pressure
3. ODS/pilot is partially clogged
1. Gas leak. SeeWarning statement at
top of page
2. Control valve defective
1. Foreign matter between control valve
and burner
2. Gas leak. SeeWarning statement at
top of page
1. Not enough combustion/ventilation air
OBSERVED PROBLEM
Heater produces a clicking/ticking noise
just after burner is lit or shut off
Heater produces unwanted odors
Heater shuts off in use (ODS operates)
Gas odor even when control knob is in OFF
position
Gas odor during combustion
Moisture/condensationnoticedonwindows
REMEDY
1. This is common with most heaters. If
noise is excessive, contact qualified ser-
vice person
1. Ventilate room. Stop using odor caus-
ing products while heater is running
2. Refill supply tank
3. Locate and correct all leaks (see Check-
ing Gas Connections, page 12)
1. Open windowand/or doorforventilation
2. Contact local natural or propane/LP gas
company
3. Clean ODS/pilot (see Cleaning and
Maintenance, page 15)
1. Locate and correct all leaks (see Check-
ing Gas Connections, page 12)
2. Replace control valve
1. Take apart gas tubing and remove for-
eign matter
2. Locate and correct all leaks (see Check-
ing Gas Connections, page 12)
1. Refer to Air for Combustion and Venti-
lation requirements (page 4)
IMPORTANT: Operating heater where impurities in air exist may create odors. Cleaning
supplies, paint, paint remover, cigarette smoke, cements and glues, new carpet or textiles,
etc., create fumes. These fumes may mix with combustion air and create odors.

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20
ILLUSTRATED PARTS
BREAKDOWN
MODELS
CBN20
CBP20
ILLUSTRATED PARTS BREAKDOWN
Models CBN20 and CBP20
2
3
56
8
9
9
10
11
12
13
14
16
18
19
4
7
1
21
20
15
17
22