Desa Comfort Glow CGN20T Quick start guide

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BLUE FLAME VENT-FREE NATURALGAS HEATER
OWNER’S OPERATION AND INSTALLATION MANUAL
WARNING: If the information in this manual is
not followed exactly, a fire or explosion may
result causing 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;donotuse
any phone in your building.
• Immediately call your gas supplier from a
neighbor’s phone. Follow the gas supplier’s
instructions.
• Ifyou cannot reach yourgas supplier, call the
fire department.
— Installation and service must be performed by
a qualified installer, service agency, or the
gas supplier.
WARNING: This is an
unvented gas-fired heater.
It uses air (oxygen) from
the room in which it is
installed. Provisions for
adequate combustion
must be provided. Refer to
page 5 of this manual
This appliance may be in-
stalled in an aftermarket*
manufactured (mobile) home,
where not prohibited by state
or local codes.
* Aftermarket: Completion of sale,
not for purpose of resale, from the
manufacturer
This appliance is only for use
with the type of gas indicated
on the rating plate. This appli-
ance is not convertible for
use with other gases.
Heater Sizes: 20,000 Btu/Hr Thermostat and
30,000 Btu/Hr Thermostat Model Heaters
®
CGN20T
CGN20TL
CGN30T
CGN30TL

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103873
CONTENTS SECTION PAGE
SAFETY
INFORMATION
WARNING ICON G 001
WARNINGS
IMPORTANT: Read this owner’s manual carefully and completely be-
foretryingtoassemble, operate,or servicethis heater.Improper useof
thisheatercancauseseriousinjuryordeathfromburns,fire,explosion,
electrical shock, and carbon monoxide poisoning.
WARNING ICON G 001
DANGER
Carbon monoxide poisoning may lead to death!
Carbon Monoxide Poisoning: Early signs of carbon monoxide poisoning
resemble the flu, with headaches, dizziness, or nausea. 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, people with heart or lung disease or anemia, those under the
influence of alcohol, and those at high altitudes.
Natural Gas: Natural gas is odorless. An odor-making agent is added to natural
gas. The odor helps you detect a natural gas leak. However, the odor added to
natural gas can fade. Natural gas may be present even though no odor exists.
Make certain you read and understand all Warnings. Keep this manual for refer-
ence. It is your guide to safe and proper operation of this heater.
Safety Information.......................................................................................2
Product Identification ..................................................................................4
Local Codes .................................................................................................4
Unpacking....................................................................................................4
Product Features ..........................................................................................4
Fresh Air For Combustion And Ventilation ................................................5
Installing To Wall........................................................................................9
Connecting To Gas Supply..........................................................................14
Checking Gas Connections..........................................................................15
Operating Heater .........................................................................................17
Inspecting Burner ........................................................................................20
Cleaning And Maintenance .........................................................................22
Troubleshooting...........................................................................................22
Technical Service ........................................................................................26
Specifications ..............................................................................................26
Service Hints ...............................................................................................26
Service Publications ....................................................................................26
Replacement Parts .......................................................................................27
Parts Centrals...............................................................................................27
Illustrated Parts List.....................................................................................28-29
Accessories ..................................................................................................30
Warranty Information ..................................................................................Back Cover
Safety Information continues on next page

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103873
SAFETY
INFORMATION
Continued
WARNING ICON G 001
WARNINGS Continued
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. 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
3. This heater shall not be installed in a bedroom or bathroom.
4. Never install the heater
• in a recreational vehicle
• where curtains, furniture, clothing, or other flammable 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
5. This heater needs fresh, outside air ventilation to run properly. This heater has
an oxygen depletion sensor (ODS) pilot light safety system. The ODS shuts
down the heater if not enough fresh air is available. See Fresh Air for Combus-
tion and Ventilation, pages 5 through 8.
6. Keep air openings in front and bottom of heater clear and free of debris. This will
ensure enough air for proper combustion.
7. If heater shuts off, do not relight until you provide fresh, outside 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. Never place any objects on the heater.
10.Surface of heater becomes very hot when running heater. Keep children and
adults away from hot surface to avoid burns or clothing ignition. Heater will
remain hot for a time after shut-down. Allow surface to cool before touching.
11.Carefully supervise young children when they are in the same room with
heater.
12.Make sure grill guard is in place before running heater.
13.Do not use heater if any part has been under water. Immediately 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.
14.Turn off and unplug heater and let cool before servicing. Only a qualified
service person should service and repair heater.
15.Operating heater above elevations of 4,500 feet could cause pilot outage.

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103873
PRODUCT
IDENTIFICATION
LOCAL CODES Install and use heater with care. Follow all local codes. In the absence of local codes, use
the latest edition of the National Fuel Gas Code ANSI Z223, also known as 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 Natural Gas Heater (30,000 Btu/Hr Model Shown)
Ignitor Button Control Knob
Heater
Cabinet
Front
Panel
Glass
Panel
Grill
Guard
UNPACKING 1. Remove heater from carton.
2. Remove all protective packaging applied to heater for shipment.
3. Check heater for any shipping damage. If heater is damaged, promptly inform
dealer where you bought heater.
PRODUCT
FEATURES
Safety Device
This heater has a pilot with an Oxygen Depletion Sensor Shutoff System (ODS). 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 have a thermostat sensing bulb and a control valve. This results in
the greatest heater comfort. This can also result in lower gas bills.

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103873
FRESH AIR
FOR
COMBUSTION
AND
VENTILATION
WARNING ICON G 001
WARNING
This heater shall not be installed in a confined space unless provi-
sions are provided for adequate combustion and ventilation air.
Read the following instructions to insure proper fresh air for this
and other fuel-burning appliances in your home.
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. 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.
Exhaust fans, fireplaces, clothes dryers, and fuel burning appliances draw air from
the house to operate. You must provide adequate fresh air for these appliances. This
will insure proper venting of vented fuel-burning appliances.
Continued
Confined and Unconfined Space
The National Fuel Gas Code (ANSIZ2123.1, 1992 Section 5.3) 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 a space whose volume is not 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. Rooms communicating directly with the space in
which the appliances are installed*, through openings not furnished with doors, are
considered a part of the unconfined space.
* Adjoining rooms are communicating only if there are doorless passageways or
ventilation grills between them.
** Cubic feet equals length x width x height of room.
PROVIDING ADEQUATE VENTILATION
The following is exerpts from National Fuel Gas Code. NFPA 54/ANSI Z223.1,
Section 5.3, Air for Combustion and Ventilation.
All spaces in homes fall into one of the three following ventilation classifications:
1. Unusually Tight Contruction; 2. Unconfined Space; 3. Confined Space.
The information on pages 5 through 7 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.
Unusually tight construction is defined as construction where:
a. walls and ceilings exposed to the outside atmosphere have a continu-
ous water vapor retarder with a rating of one perm (6x10-11 per pa-sec-
m2) or less with openings gasketed or sealed and
b. weather stripping has been added on openable windows and doors and
c. caulkingorsealantsareappliedtoareassuchasjointsaroundwindowand
door frames, between sole plates and floors, between wall-ceiling joints,
betweenwallpanels,atpenetrationsforplumbing,electrical,andgaslines,
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 8 .
If your home does not meet all of the three criteria above, proceed to page 6.

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103873
FRESH AIR
FOR
COMBUSTION
AND
VENTILATION
Continued
DETERMINING FRESH-AIR FLOW FOR HEATER LOCATION
Determining if You Have a Confined or Unconfined Space
Use this worksheet to determine if you have a confined or unconfined space.
Space: Includes the room in which you will install heater plus any adjoining 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)
If additional ventilation to adjoining room is supplied with grills or openings, add
the volume of these rooms to the total volume of the space.
2. Divide the space volume by 50 cubic feet to determine the maximum Btu/Hr the
space can support.
___________ (volume of space) ÷50 cu. ft. = (Maximum Btu/Hr the space can
support)
Example: 2560 cu. ft. (volume of space) ÷50 cu. ft. = 51.2 or 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
Example: Gas water heater 40,000 Btu/Hr
Vent-free heater +20,000 Btu/Hr
Total =60,000 Btu/Hr
* Do not include direct-vent gas appliances. Direct-vent draws combustion air
from the outdoors and vents to the outdoors.
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 room or add ventilation
grills between rooms. See Ventilation Air From Inside Building, page 7.
B. Vent room directly to the outdoors. See Ventilation Air From Outdoors, page 8.
C. Install a lower Btu/Hr heater, if lower Btu/Hr size makes room unconfined.
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.

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103873
FRESH AIR
FOR
COMBUSTION
AND
VENTILATION
Continued
WARNING ICON G 001
WARNING
If the area in which the heater may be operated is smaller than that
defined as an unconfined space, provide adequate combustion and
ventilation air by one of the methods described in the National Fuel
Gas Code, ANSI Z223.1, 1992, Section 5.3 or applicable local codes .
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 NFPA 54/ANSI
Z223.1, Section 5.3, Air for Combustion and Ventilation for required size of ventila-
tion grills or ducts.
WARNING ICON G 001
WARNING
Rework worksheet, adding the space of the adjoining unconfined
space. The combined spaces must have enough fresh air to supply all
appliances in both spaces.
Figure 2 - Ventilation Air from Inside Building
Continued
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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103873
FRESH AIR
FOR
COMBUSTION
AND
VENTILATION
Continued
Figure 3 - Ventilation Air from Outdoors
Ventilation Air From Outdoors
Provide extra fresh air by using ventilation grills or ducts. You must provide two
permanent openings: one within 12" of the ceiling and one within 12" of the floor.
Connect these items directly to the outdoors or spaces open to the outdoors. These
spaces include attics and crawl spaces.
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.
Outlet
Air Ventilated
Attic
Outlet
Air
Inlet
Air
Inlet Air Ventilated
Crawl Space
To
Crawl
Space
To Attic

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103873
INSTALLINGTO
WALL NOTICE
A qualified service person must install heater. Follow all local codes.
CHECK GAS TYPE
Use only natural gas. If your gas supply is not natural gas, do not install heater. Call
dealer where you bought heater for proper type heater.
INSTALLATION ITEMS
Before installing heater, make sure you have the items listed below.
• piping (check local codes)
• sealant (resistant to propane/LP gas)
• manual shutoff valve *
• ground joint union
• test gauge connection * (see
Figure 12, page 15)
• sediment trap
• tee joint
• pipe wrench
* An A.G.A. design-certified manual shutoff valve with 1/8" NPT tap is an acceptable
alternative to test gauge connection. Purchase the optional A.G.A. design-certified
manual shutoff valve from your dealer. See Accessories, page 30.
LOCATING HEATER
This heater is designed to be mounted on a wall.
WARNING ICON G 001
WARNING
Maintain the minimum clearances shown in Figure 4 (page 10). If you
can, provide greater clearances 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 30.
WARNING ICON G 001
WARNING
Never install the heater
• in a bedroom or a bathroom
• in a recreational vehicle
• where curtains, furniture, clothing, or other flammable 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
WARNING ICON G 001
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 coverings or operating heater where impurities in the air (such
as tobacco smoke) exist, may discolor walls.
Continued
IMPORTANT: Vent-free heaters add moisture to the air. Although this is beneficial,
installing heater in rooms without enough ventilation air may cause mildew to form
from too much moisture. See Fresh Air for Combustion and Ventilation, pages 5
through 8.

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103873
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, page 30. If plan-
ning to use fan, locate heater near an electrical outlet.
Figure 4 - Mounting Clearances As Viewed From Front of Heater
INSTALLINGTO
WALL
Continued
WARNING ICON G 001
CAUTION
If you install the heater in a home garage
• heater pilot and burner must be at least 18 inches above floor
• locate heater where moving vehicle will not hit it
Minimum
From
Sides Of
Heater
36"
3"
FLOOR
CEILING
Minimum
Minimum To Top Surface
Of Carpeting, Tile Or Other
Combustible Material
6"
Left
Side Right
Side
Figure 5 - Attaching Thermostat Sensing Bulb
Clamp
Thermostat
Sensing Bulb
THERMOSTAT SENSING BULB
The thermostat sensing bulb has been placed inside the heater for protection during
shipping.
Locating Thermostat Sensing Bulb
1. Remove front panel of heater (see Figure 7, page 11).
2. Locate thermostat sensing bulb just under burner assembly.
IMPORTANT: Attach thermostat sensing bulb to back of heater for 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.

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103873
INSTALLING HEATER TO WALL
Mounting Bracket
The mounting bracket is located on back panel of heater. It has been taped there for
shipping. Remove mounting bracket from back panel.
Continued
Figure 6 - Bracket Location
Mounting
Bracket
INSTALLINGTO
WALL
Continued
Figure 7 - Removing Front Panel Of Heater
Methods For Attaching Mounting Bracket To Wall
Only use last hole on each end of mounting bracket to attach bracket to wall. These
two holes are 16 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. Insert mounting
screws through mounting bracket and into wall studs.
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.
Removing Front Panel Of Heater
1. Remove two screws near bottom corners of front panel.
2. Lift straight up on grill guard until it stops. Grill guard will slide up about 1/4".
3. Pull bottom of front panel forward, then downward.
4. Remove cardboard packing from grill and glass.

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103873
Marking Screw Locations
1. Tape mounting bracket to wall where heater will be located. Make sure mounting
bracket is level.
30,000 Btu/Hr Model 20,000 Btu/Hr Models
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
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.
Attaching to wall anchor method
For attaching mounting bracket to hollow walls (wall areas between 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.
INSTALLINGTO
WALL
Continued
Figure 9 - Folding Anchor
WARNING
Maintain minimum clearances shown in Figure 8. If you can, provide
greater clearances from floor and joining wall.
18 3/4"
Min.
11"
Min. 16"
18 3/4"
Min.
7 1/4"
Min.
Adjoining Wall
16"
Adjoining Wall
Only Insert Mounting
Screws Through Last
Hole On Each End
Only Insert Mounting
Screws Through Last
Hole On Each End
Floor Floor

13
103873
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.
Figure 10 - Popping Open Anchor Wings For Thin Walls
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. Tighten screws until mounting bracket is firmly fastened 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
Stand-Out Tab
Horizontal Slots
Mounting Bracket
(attached to wall)
Installing Bottom Mounting Screws
1. Locate two bottom mounting holes. These holes are near bottom 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 Attaching To Wall Anchor Method, page 12.
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 14-16). Make gas connections and
check for leaks before replacing front panel (see pages 14-16).
Figure 12 - Installing Bottom Mounting Screws
INSTALLINGTO
WALL
Continued

14
103873
CONNECTING
TO GAS
SUPPLY
NOTICE
A qualified service person must connect heater to gas supply. Fol-
low all local codes.
Typical Inlet Pipe Diameters
20,000 Btu/Hr Models 3/8" or greater
30,000 Btu/Hr Model 1/2" or greater
Installation must include a manual 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 13, page 15).
Apply pipe joint sealant lightly to male 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 13, page 15. Locate sediment
trap where it is within reach for cleaning. Locate sediment trap where trapped matter
is not likely to freeze. A sediment trap traps moisture and contaminants. This keeps
them from going into heater controls. If sediment trap is not installed or is installed
wrong, heater may not run properly.
IMPORTANT : 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 ICON G 001
CAUTION
Use only new, black iron or steel pipe. Internally-tinned copper
tubing may be used in certain areas. Check your local codes. Use
pipe of large enough diameter to allow proper gas volume to heater.
If pipe is too small, undue loss of pressure will occur.
WARNING ICON G 001
CAUTION
Use pipe joint sealant that is resistant to liquid petroleum (LP) gas.
WARNING ICON G 001
WARNING
Never connect heater to private (non-utility) gas wells. This gas is
commonly known as well-head gas.

15
103873
IMPORTANT: Holdpressureregulatorwithwrenchwhenconnectingittogaspipingand/
or fittings.
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
Figure 13 - Gas Connection
* An A.G.A. design-certified manual shutoff valve with 1/8" NPT tap is an acceptable
alternative to test gauge connection. Purchase the optional A.G.A. design-certified
manual shutoff valve from your dealer. See Accessories, page 30.
Heater
Cabinet
Sediment
Trap
WARNING ICON G 001
WARNING
Test all gas piping and connections for leaks after installation or
servicing. Correct all leaks at once.
Continued
Manual
Shutoff
Valve *
CONNECTING
TO GAS
SUPPLY
Continued
3" Minimum
Typical Inlet Pipe from
Gas Meter
(4" W.C. to
10.5" W.C. Pressure)
WARNING ICON G 001
WARNING
Never use an open flame to check for a leak. Apply a mixture of
liquid soap and water to all joints. Bubbles forming show a leak.
Correct all leaks at once.
PRESSURE TESTING GAS SUPPLY PIPING SYSTEM
Test Pressures In Excess Of 1/2 PSIG
1. Disconnect heater and its individual manual shutoff valve from gas supply piping
system. Pressures in excess of 1/2 psig will damage heater regulator.
2. Cap off open end of gas pipe where manual shutoff valve was connected.
3. Pressurize supply piping system by either using compressed air or
opening main gas valve located on or near gas meter.
CHECKING
GAS
CONNECTIONS
Ground Joint Union

16
103873
ON
POSITION
OFF
POSITION
4. Check all joints of gas supply piping system. Apply mixture of liquid soap and
water to gas joints. Bubbles forming show a leak.
5. Correct all leaks at once.
Test Pressures Equal To or Less Than 1/2 PSIG
1. Close manual shutoff valve (see Figure 14).
2. Pressurize supply piping system by either using compressed air or opening main
gas valve located on or near gas meter.
3. Check all joints from gas meter to manual shutoff valve (see Figure 15). Apply
mixture of liquid soap and water to gas joints. Bubbles forming show a leak.
4. Correct all leaks at once.
PRESSURE TESTING HEATER GAS CONNECTIONS
1. Open manual shutoff valve (see Figure 14).
2. Open main gas valve located on or near gas meter.
3. Make sure control knob of heater is in the OFF position.
4. Check all joints from manual shutoff valve to thermostat gas valve (see Figure 15).
Apply mixture of liquid soap and water to gas joints. Bubbles forming show a
leak.
5. Correct all leaks at once.
6. Light heater (see Operating Heater, pages 17 through 19). Check the rest of the
internal joints for leaks.
7. Turn off heater (see To Turn Off Gas to Appliance, page 19).
8. Replace front panel.
Figure 14 - Manual Shutoff Valve
Manual
Shutoff
Valve
Open
Closed
Thermostat Gas Valve
Gas Meter
Figure 15 - Checking Gas Joints
CHECKING
GAS
CONNECTIONS
Continued
Manual
Shutoff
Valve

17
103873
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 IF YOU 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 department.
C. Use only your hand to push in or turn the gas control knob. Never use tools.
If the knob will not push in or turn by hand, don’t try to repair it, call a
qualified service technician 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.
Continued
WARNING ICON G 001
WARNING
If you do not follow these instructions exactly, a fire or explosion
may result causing property damage, personal injury or loss of life.
PILOT
LO
OFF
HI
IGNITOR
Ignitor Button Control Knob
Figure 16 - Control Knob In The OFF Position
LIGHTING INSTRUCTIONS
1. STOP! Read the safety information above.
2. Make sure manual shutoff valve is fully open.
3. Turn control knob clockwise
Clockwise
to the OFF position.

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103873
4. Wait five (5) 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 at the
top of page 17. If you don’t smell gas, go to the next step.
5. Turn control knob counterclockwise
C-clockwise
to the PILOT position. Press in
control knob for five (5) seconds (see Figure 16).
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.
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 ignitor button. This will
light pilot. The pilot is attached to the front of burner. The pilot can be seen
through the glass panel. If needed, keep pressing ignitor button until pilot
lights.
Note: If pilot does not stay lit, refer to Troubleshooting, pages 22 through
25. Also contact a qualified service person or gas supplier for repairs. Until
repairs are made, light pilot with match. To light pilot with match, see
Manual Lighting Procedure, page 19.
7. Keep control knob pressed in for 30 seconds after lighting pilot. After 30
seconds, release control knob.
OPERATING
HEATER
WARNING ICON G 001
CAUTION
Do not try to adjust heating levels by using the manual shutoff valve.
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
C-clockwise
to desired heating level. The
main burner should light. Set control knob to any heat level between HI and
LO.
Thermocouple
Ignitor Electrode
Figure 17 - Pilot
Pilot Burner

19
103873
TO TURN OFF GAS TOAPPLIANCEOPERATING
HEATER Shutting Off Heater
1. Turn control knob clockwise
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)
1. Turn control knob clockwise
Clockwise
to the PILOT position.
THERMOSTAT CONTROL OPERATION
The thermostatic control used on these models differs from standard thermo-
stats. 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 flame
height. At times the room may exceed the set temperature. 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.
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, installation location, room size, open air temperatures,
etc.). Frequent use of your heater will let you determine your own comfort levels.
MANUAL LIGHTING PROCEDURE
1. Remove front panel (see Figure 7, page 11).
2. Follow steps 1 through 5 under Lighting Instructions, pages 17 and 18.
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.
5. Replace front panel.

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103873
INSPECTING
BURNER
Check pilot flame pattern and burner flame pattern often.
PILOT FLAME PATTERN
Figure 18 shows a correct pilot flame pattern. Figure 19 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.
Thermocouple Pilot Burner
Figure 18 - Correct Pilot Flame Pattern
Pilot Burner
Thermocouple
Figure 19 - Incorrect Pilot Flame Pattern
If pilot flame pattern is incorrect, as shown in Figure 19.
• turn heater off (see To Turn Off Gas to Appliance, page 19).
• see Troubleshooting, pages 22 through 25.