Desa CDL3924NT Quick start guide

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For more information, visit www.desatech.com
WARNING: If the information in this manual is not fol-
lowed 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.
• 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.
— Installation and service must be performed by a quali-
fied installer, service agency or the gas supplier.
UNVENTED (VENT-FREE) GAS LOG HEATER
OWNER’S OPERATION AND INSTALLATION MANUAL
24" VARIABLE MANUALLY-
CONTROLLED MODELS
LSL3124N AND LSL3124P
Echo Valley Oak Log Design
24" VARIABLE
THERMOSTATICALLY-
CONTROLLED MODELS
CDL3924NT AND CDL3924PT
Meadowbrook Oak Log Design

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2
WARNING: Improper installation, adjustment, altera-
tion, service or maintenance can cause injury or prop-
erty damage. Refer to this manual for correct installation
and operational procedures. For assistance or addi-
tional information consult a qualified installer, service
agency or the gas supplier.
WARNING: This appliance is for installation only in a
solid-fuel burning masonry or UL127 factory-built fire-
place or in a listed ventless firebox enclosure. It is de-
sign-certified for these installations in accordance with
ANSI Z21.11.2. Exception: Do not install this appliance in
a factory-built fireplace that includes instructions stat-
ing it has not been tested or should not be used with
unvented gas logs.
WARNING: This is an unvented gas-fired heater. It uses
air (oxygen) from the room in which it is installed. Provi-
sions for adequate combustion and ventilation air must
be provided. Refer to Air for Combustion and Ventilation
section on page 5 of this manual.
This appliance may be installed in an aftermarket,* per-
manently located, manufactured (mobile) home, where
not prohibited by local codes.
This appliance is only for use with the type of gas indi-
cated on the rating plate. This appliance is not convert-
ible for use with other gases.
* Aftermarket: Completion of sale, not for purpose of resale, from the manufacturer
TABLE OF CONTENTS
Safety Information ............................................... 3
Local Codes ........................................................ 4
Unpacking ........................................................... 4
Product Identification ........................................... 5
Product Features ................................................. 5
Air For Combustion and ventilation ..................... 5
Installation ........................................................... 8
Operating heater ............................................... 16
Manually-Controlled Models .............................. 16
Inspecting burners ............................................. 20
Cleaning and Maintenance ................................ 21
Troubleshooting ................................................. 22
Optional Positioning of Thermostat Sensing Bulb ... 25
Specifications .................................................... 26
Accessories ....................................................... 27
Service Hints ..................................................... 27
Technical Service .............................................. 27
Replacement Parts ............................................ 27
Illustrated Parts Breakdown and Parts List ....... 28
Warranty Information ......................................... 32

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111347-01E 3
SAFETY INFORMATION
WARNING: This product con-
tains and/or generates chemicals
known to the State of California
to cause cancer or birth defects
or other reproductive harm.
IMPORTANT: Read this owner’s
manual carefully and completely
before trying to assemble,
operate or service 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!
Carbon Monoxide Poisoning: Early signs of carbon
monoxide poisoning resemble the flu, with head-
aches, 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 and Propane/LP Gas: Natural and pro-
pane/LP gases are odorless. An odor-making agent
is added to the gas. The odor helps you detect a gas
leak. However, the odor added to the gas can fade.
Gas may be present even though no odor exists.
Make certain you read and understand all warn-
ings. Keep this manual for reference. It is your
guide to safe and proper operation of this heater.
WARNING: Any change to
this heater or its controls can
be dangerous.
WARNING: Do not use a
blower insert, heat exchanger
insert or other accessory not ap-
proved for use with this heater.
WARNING: Do not allow fans
to blow directly into the fireplace.
Avoid any drafts that alter burner
flame patterns. Ceiling fans can
create drafts that alter burner
flame patterns. Altered burner
patterns can cause sooting.
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 or near
the appliance. Never place any
objects on the heater.
Heater base assembly 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
shutdown. Allow surface to cool
before touching.
You must operate this heater
with a fireplace screen in place.
Make sure fireplace screen is
closed before running heater.
Keep the appliance area clear
and free from combustible ma-
terials, gasoline and other flam-
mable vapors and liquids.
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) in-
side any structure. Locate propane/LP supply
tank(s) outdoors (propane/LP units only).

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SAFETY INFORMATION
Continued
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 neighborʼs phone. Follow the gas
supplierʼs instructions
• if you cannot reach your gas supplier, call
the fire department
4. This heater shall not be installed in a bedroom
or bathroom, unless installed as a vented appli-
ance. See Installing Damper Clamp Accessory
for Vented Operation, page 11.
5. Before installing in a solid fuel burning fireplace,
the chimney flue and firebox must be cleaned
of soot, creosote, ashes and loose paint by a
qualified chimney cleaner. Creosote will ignite if
highly heated. Inspect chimney flue for damage.
If damaged, repair flue before operating heater.
6. Do not burn solid-fuel in a masonry or UL127
factory-built fireplace in which a vent-free
room heater is installed.
7. If fireplace has glass doors, never operate this
heater with glass doors closed. If you operate
heater with doors closed, heat buildup inside
fireplace will cause glass to burst. Make sure there
are no obstructions across opening of fireplace.
8. To prevent the creation of soot, follow the instruc-
tions in Cleaning and Maintenance, page 21.
9. Before using furniture polish, wax, carpet
cleaner or similar products, turn heater off. If
heated, the vapors from these products may
create a white powder residue within burner
box or on adjacent walls and furniture.
10. This heater needs fresh, outside air ventilation
to run properly. This heater has an Oxygen
Depletion Sensing (ODS) safety shutoff sys-
tem. The ODS shuts down the heater if enough
fresh air is not available. See Air for Combus-
tion and Ventilation, page 5. If heater keeps
shutting off, see Troubleshooting, page 22.
11. Do not run heater
• where flammable liquids or vapors are
used or stored
• under dusty conditions
12. Do not use this heater to cook food or burn
paper or other objects.
13. Do not use heater if any part has been exposed
to or 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. Do not operate heater if any log is broken. Do
not operate heater if a log is chipped (dime-
sized or larger).
15. Turn heater off and let cool before servicing,
installing or repairing. Only a qualified service
person should install, service or repair heater.
16. Operating heater above elevations of 4,500
feet may cause pilot outage.
17. To prevent performance problems, do not
use propane/LP fuel tank of less than 100 lb.
capacity (propane/LP units only).
18. Provide adequate clearances around air
openings.
LOCAL CODES
Install and use heater with care. Follow all local
codes. In the absence of local codes, use the lat-
est edition of the National Fuel Gas Code 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
Note: Where listed vented decorative logs are
required, thermostat operation is not permitted.
State of Massachusetts: The installa-
tion must be made by a licensed plumber
or gas fitter in the Commonwealth of
Massachusetts.
Sellers of unvented propane or natural
gas-fired supplemental room heaters shall
provide to each purchaser a copy of 527
CMR 30 upon sale of the unit.
Vent-free gas products are prohibited for
bedroom and bathroom installation in the
Commonwealth of Massachusetts.
UNPACKING
CAUTION: Do not remove the
data plates from the grate as-
sembly. The data plates contain
important warranty and safety
information.
1. Remove logs and heater base assembly from
carton. Note: Do not pick up heater base as-
sembly by burners. This could damage heater.
Always handle base assembly by grate.
2. Remove all protective packaging applied to
logs and heater for shipment.
3. Check all items for any shipping damage. If
damaged, promptly inform dealer where you
bought heater.

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111347-01E 5
Figure 1 - Product Identification
Meadowbrook Oak Logs with Thermostat
Control
Echo Valley Oak Logs with Manual
Control
Control
Knob
Control
Cover Log
Control
Cover Log
Piezo Ignitor
(behind log)
Piezo Ignitor
(behind log)
Control
Knob
PRODUCT
IDENTIFICATION
PIEZO IGNITION SYSTEM
This heater has a piezo ignitor. This system re-
quires no matches, batteries or other sources to
light heater.
AIR FOR COMBUSTION
AND VENTILATION
WARNING: This heater shall not
be installed in a confined space
or unusually tight construction
unless provisions 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.
Todayʼs 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 effi-
cient, 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.
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 fol-
lowing ventilation classifications:
1. Unusually Tight Construction
2. Unconfined Space
3. Confined Space
The information on pages 5 through 7 will help
you classify your space and provide adequate
ventilation.
PRODUCT FEATURES
OPERATION
This heater is clean burning. It requires no outside
venting. There is no heat loss out a vent or up a
chimney. Heat is generated by realistic flames. This
heater is designed for vent-free operation with flue
damper closed. It has been tested and approved
to ANSI Z21.11.2 standard for unvented heaters.
State and local codes in some areas prohibit the
use of vent-free heaters. This heater may also be
operated as a vented decorative (ANSI Z21.60)
product by opening the flue damper.
SAFETY DEVICE
This heater has a pilot with an Oxygen Deple-
tion 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.

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AIR FOR COMBUSTION
AND VENTILATION
Continued
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 out-
side atmosphere have a continuous
water vapor retarder with a rating of one
perm (6 x 10-11 kg 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. caulking or sealants are applied to areas
such as joints around window and door
frames, between sole plates and floors,
between wall-ceiling joints, between
wall panels, at penetrations for plumb-
ing, 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 7.
If your home does not meet all of the three
criteria above, proceed to Determining
Fresh-Air Flow For Heater Location.
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 m3 per 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 m3 per kw) of the aggregate input rating of
all appliances installed in that space. Rooms com-
municating 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.
DETERMINING FRESH-AIR FLOW
FOR HEATER LOCATION
Determining if You Have a Confined or
Unconfined Space
Use this work sheet 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. Multiply the space volume by 20 to determine
the maximum Btu/Hr the space can support.
__________ (volume of space) x 20 = (Maxi-
mum 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. Di-
rect-vent draws combustion air from the outdoors
and vents to the outdoors.
Example:
Gas water heater __________ Btu/Hr
Vent-free fireplace + ________ Btu/Hr
Total = ________ Btu/Hr
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)
73,000 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
40,000
33,000
73,000

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111347-01E 7
AIR FOR COMBUSTION
AND VENTILATION
Continued
Figure 3 - Ventilation Air from Outdoors
Figure 2 - Ventilation Air from Inside
Building
Outlet
Air
Ventilated
Attic
Outlet
A
ir
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
Ventilation
Grills
Into Adjoining
Room,
Option 1
12"
12"
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.
B. Vent room directly to the outdoors. See Ven-
tilation Air From Outdoors.
C. Install a lower Btu/Hr fireplace, if lower Btu/Hr
size makes room unconfined.
If the actual Btu/Hr used is less than the maxi-
mum Btu/Hr the space can support, the space is
an unconfined space. You will need no additional
fresh air ventilation.
WARNING: If the area in which
the heater may be operated is
smaller than that defined as
an unconfined space or if the
building is of unusually tight
construction, provide adequate
combustion and ventilation air
by one of the methods described
in the National Fuel Gas Code,
ANSI Z223.1/NFPA 54 Section 5.3
or applicable local codes.
VENTILATION AIR
Ventilation Air From Inside Building
This fresh air would come from an adjoining un-
confined space. When ventilating to an adjoining
unconfined space, you must provide two perma-
nent 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
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. 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.

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8
INSTALLATION
NOTICE: This heater is intended
for use as supplemental heat.
Use this heater along with your
primary heating system. Do not
install this heater as your pri-
mary 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 throughout the
house. In the event of a power
outage, you can use this heater
as your primary heat source.
WARNING: A qualified service
person must install heater. Fol-
low all local codes.
NOTICE: State or local codes
may only allow operation of this
appliance in a vented configura-
tion. Check your state or local
codes.
WARNING: Before installing
in a solid fuel burning fireplace,
the chimney flue and firebox
must be cleaned of soot, creo-
sote, ashes and loose paint by
a qualified chimney cleaner.
Creosote will ignite if highly
heated. A dirty chimney flue and
firebox may create and distribute
soot within the house. Inspect
chimney flue for damage. If
damaged, repair flue before
operating heater.
WARNING: Seal any fresh air
vents or ash clean-out doors lo-
cated on floor or wall of fireplace.
If not, drafting may cause pilot
outage or sooting. Use a heat-
resistant sealant. Do not seal
chimney flue damper.
WARNING: Never install the
heater
• in a bedroom or bathroom
unless installed as a vented
appliance, see page 11
• in a recreational vehicle
• where curtains, furniture,
clothing or other flammable
objects are less than 42 inches
from the front, top or sides of
the heater
• in high traffic areas
• in windy or drafty areas
CAUTION: This heater cre-
ates warm air currents. These
currents move heat to wall sur-
faces next to heater. 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 flu-
ids, oil or kerosene lamps, etc.) in
the air exist, may discolor walls
or cause odors.
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 Air
for Combustion and Ventilation, page 5.
CHECK GAS TYPE
Use the correct gas type (natural or propane/LP)
for your unit. If your gas supply is not correct, do
not install log set. Call dealer where you bought
log set for proper type fireplace.
WARNING: This appliance
is equipped for (natural or pro-
pane/LP) gas. Field conversion
is not permitted.

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111347-01E 9
INSTALLATION AND CLEARANCES
FOR VENT-FREE OPERATION
WARNING: Maintain the mini-
mum clearances. If you can, pro-
vide greater clearances from floor,
ceiling and adjoining wall.
INSTALLATION
Continued
LOG SIZING REQUIREMENTS
Minimum Firebox
Height Depth Front Rear *
Width Width
17" 14" 28" 21"
* Measured at 14" depth.
MINIMUM FIREPLACE CLEARANCE TO
COMBUSTIBLE MATERIALS
Side Wall Ceiling
16" 42"
Carefully follow the instructions below. This will
ensure safe installation into a masonry, UL127-listed
manufactured fireplace or listed vent-free firebox.
Minimum Clearances For Side Combustible
Material, Side Wall and Ceiling
A. Clearances from the side of the fireplace
cabinet to any combustible material and wall
should follow diagram in Figure 4.
Example: The face of a mantel, bookshelf,
etc. is made of combustible material and
protrudes 3 1/2" from the wall. This combus-
tible material must be 4" from the side of the
fireplace cabinet (see Figure 4).
Note: When installing your gas logs into
a manufactured firebox, follow firebox
manufacturerʼs instructions for minimum
clearances to combustible materials.
B. Clearances from the top of the fireplace opening
to the ceiling should not be less than 42 inches.
Figure 4 - Minimum Clearance for
Combustible to Wall
*Minimum 16 inches from Side Wall
Example
NOTICE: Manual control heaters
may be used as a vented product.
If so, you must always run heater
with chimney flue damper open.
If running heater with damper
open, noncombustible material
above fireplace opening is not
needed. Go to Installing Damper
Clamp Accessory for Vented
Operation, page 11.
MINIMUM NONCOMBUSTIBLE
MATERIAL CLEARANCES
If Not Using Mantel
Note: If using a mantel proceed to If Using Mantel.
If not using a mantel, follow the information on
this page.
You must have noncombustible material(s) above
the fireplace opening. Noncombustible materials
(such as slate, marble, tile, etc.) must be at least
1/2 inch thick. With sheet metal, you must have
noncombustible material behind it. Noncombustible
material must extend at least 8" up (for all models).
If noncombustible material is less than 12", you
must install the fireplace hood accessory. See Figure
5, page 10, for minimum clearances.
If Using Mantel
You must have noncombustible material(s) above
the fireplace opening. Noncombustible materials
(such as slate, marble, tile, etc.) must be at least
1/2 inch thick. With sheet metal, you must have
noncombustible material behind it. Noncombus-
tible material must extend at least 8 inches up).
If noncombustible material is less than 12", you
must install the fireplace hood accessory. Even if
noncombustible material is more than 12", you may
need the hood accessory to deflect heat away from
your mantel shelf. See Figures 5, 6 and 7, page 10,
for minimum clearances.
IMPORTANT: If you cannot meet these minimum
clearances, you must operate heater with chimney
flue damper open. Go to Installing Damper Clamp
Accessory for Vented Operation, page 11.
*

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10
Figure 5 - Heat Resistant Material (Slate,
Marble, Tile, etc.) Above Fireplace
Noncombus-
tible Material
Distance (A)
12" or more
Between 8" and
12"
Less than 8"
Requirements for Safe
Installation
Noncombustible Mate-
rial OK.
Install fireplace hood
accessory (GA6050,
GA6052 or GA6053 see
Accessories, page 27)
Noncombustible materi-
als must be extended to
at least 8". See
Between
8" and 12" above. If you
cannot extend material,
you must operate heater
with flue damper open.
INSTALLATION
Continued
Minimum
Noncombustible
Material
Minimum Non-
Combustible
Material Height
Distances to
Underside of
Mantel
Top of
Fireplace
Opening
Underside of
Mantel Shelf
Mantel Shelf
12"
8"
(A)
18"
8"
20"
14"
22"
17"
24"
20"
All minimum
distances are
in inches
Log Set
24"/30"/36"
Models
18" Model
2 1/2"
6"
8"
10"
MANTEL CLEARANCES
In addition to meeting noncombustible material
clearances, you must also meet required clearances
between fireplace opening and mantel shelf. If
you do not meet the clearances listed below, you
will need a hood.
Determining Minimum Mantel Clearance
If you meet minimum clearance between mantel
shelf and top of fireplace opening, a hood is not
required (see Figure 6).
Determining Minimum Mantel Clearance
When Using a Hood
If minimum clearances in Figure 6 are not met, you
must have a hood. When using a hood there are
still certain minimum mantel clearances required.
Follow minimum clearances shown in Figure 7
when using hood.
Figure 6 - Minimum Mantel Clearances
Without Using Hood
Figure 7 - Minimum Mantel Clearances
When Using Hood
Minimum
Noncombustible
Material
8"
Min.
12"
15"
18"
All minimum
distances are
in inches
20"
2 1/2"
6"
8"
10"
12"
Distances to
Underside of
Mantel
Hood
(GA6050,
GA6052 or
GA6053)
Top of
Fireplace
Opening
Underside
of Mantel
Shelf
Mantel Shelf
Hood
(GA6050,
GA6052 or
GA6053)
NOTICE: Surface temperatures
of adjacent walls and mantels be-
come hot during operation. Walls
and mantels above the firebox
may become hot to the touch.
If installed properly, these tem-
peratures meet the requirement
of the national product standard.
Follow all minimum clearances
shown in this manual.

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111347-01E 11
NOTICE: If your installation does
not meet the minimum clear-
ances shown, you must do one
of the following:
• operate the logs only with the
flue damper open
• raise the mantel to an accept-
able height
• remove the mantel
FLOOR CLEARANCES
A. If installing appliance on the floor level, you
must maintain the minimum distance of 14"
to combustibles (see Figure 8).
B. If combustible materials are less than 14" to
the fireplace, you must install appliance at
least 5" above the combustible flooring (see
Figure 9).
INSTALLATION
Continued
Figure 8 - Minimum Fireplace Clearances
If Installed at Floor Level
Figure 9 - Minimum Fireplace Clearances
Above Combustible Flooring
Hearth
5"
Min.
Combustible
Material
14"
Min.
Combustible
Material
Noncombustible Material
Noncombustible Material
INSTALLING DAMPER CLAMP
ACCESSORY FOR VENTED
OPERATION
Note: When used as a vented heater, appliance
must be installed only in a solid-fuel burning
fireplace with a working flue and constructed of
noncombustible material.
If your heater is a manually-controlled model, you may
use this heater as a vented product. There are three rea-
sons for operating your heater in the vented mode.
1. The fireplace does not meet the clearance to com-
bustibles requirements for vent-free operation.
2. State or local codes do not permit vent-free
operation.
3. You prefer vented operation.
If reasons number 1 or 2 above apply to you, you
must permanently open chimney flue damper. You
must install the damper clamp accessory (to order,
see Accessories, page 27). This will insure vented
operation (see Figure 10). The damper clamp will
keep damper open. Installation instructions are
included with clamp accessory.
See chart below for minimum permanent flue
opening you must provide. Attach damper clamp
so the minimum permanent flue opening will be
maintained at all times.
Area of Various Standard Round Flues
Diameter (ins.) Area (sq. ins.)
5" 20 sq. inches
6" 29 sq. inches
7" 39 sq. inches
8" 51 sq. inches
Figure 10 - Attaching Damper Clamp
Masonry Fireplace
Chimney Minimum Permanent
Height (ft.) Flue Opening (sq. ins.)
6' to 15' 39 sq. inches
15' to 30' 29 sq. inches
Damper
Manufactured Fireplace
Damper Clamp
Damper
Damper
Clamp
Damper

www.desatech.com 111347-01E
12
Heater Gas
Regulator Flexible Gas
Hose (if allowed
by local codes)
Fitting
INSTALLING HEATER BASE
ASSEMBLY
WARNING: You must secure
this heater to fireplace floor. If
not, heater will move when you
adjust controls. Moving heater
may cause a gas leak or log
misplacement.
WARNING: If installing in a
sunken fireplace, special care
is needed. You must raise the
fireplace floor to allow access
to heater control panel. This
will insure adequate air flow
and guard against sooting and
controls being damaged. Raise
fireplace floor with noncombus-
tible material. Make sure material
is secure.
CAUTION: Do not pick up
heater base assembly by burn-
ers. This could damage heater.
Only handle base assembly by
grates.
IMPORTANT: Make sure the heater burners are
level. If heater is not level, heater will not work
properly. For thermostat models, avoid damage
to thermostat bulb. Avoid nicks or sharp bends
in thermostat bulb wire. Keep thermostat bulb
in mounting bracket until ready to mount base
to floor. See Optional Positioning Of Thermostat
Sensing Bulb, page 25.
Installation Items Needed
• hardware package (provided with heater)
• approved flexible gas hose and fittings (not
provided) (if allowed by local codes)
• sealant (resistant to propane/LP gas, not
provided)
• electric drill with 3/16" drill bit (metal or ma-
sonry as applicable)
• flathead screwdriver
• pipe wrench
INSTALLATION
Continued
Figure 11 - Attaching Flexible Gas Hose
to Heater Gas Regulator
1. Apply pipe joint sealant lightly to male
threads of gas fitting (not provided). Connect
approved flexible gas hose to gas regulator of
heater (see Figure 11). IMPORTANT: Hold
gas regulator with wrench when connecting
flexible gas hose.
2. Locate two masonry screws in hardware
package.
3. Place heater base in fireplace.
4. Place logs in their proper position on heater
base (see Installing Logs, page 15).
5. Center heater base and logs front-to-back and
side-to-side in fireplace.
6. Carefully remove logs without moving heater
base.
7. Mark screw locations through one hole on
each side of the base (see Figure 12). If install-
ing in a brick-bottom fireplace, mark screw
locations in mortar joint of bricks.
8. Remove heater base from fireplace.
9. Drill holes at marked locations using 3/16"
drill bit.
10. Attach base assembly to fireplace floor using
two masonry screws (in hardware package).
Figure 12 - Attaching Heater to
Fireplace Floor
Masonry
Screw
Screw
Holes
in Base

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111347-01E 13
CONNECTING TO GAS SUPPLY
WARNING: This appliance
requires a 1/2" NPT (National
Pipe Thread) inlet connection to
the pressure regulator.
WARNING: A qualified service
person must connect heater to gas
supply. Follow all local codes.
CAUTION: Never connect pro-
pane/LP fireplace directly to the
propane/LP supply. This heater
requires an external regulator
(not supplied). Install the exter-
nal regulator between the heater
and propane/LP supply.
WARNING: Never connect
natural gas fireplace to private
(non-utility) gas wells. This
gas is commonly known as
wellhead gas.
Installation Items Needed
Before installing heater, make sure you have the
items listed below.
• external regulator (supplied by installer)
• piping (check local codes)
• sealant (resistant to propane/LP gas)
• equipment shutoff valve *
• test gauge connection *
• sediment trap
• tee joint
• pipe wrench
* 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 27.
For propane/LP units, the installer must supply
an external regulator. The external regulator will
reduce incoming gas pressure. You must reduce
incoming gas pressure to between 11 and 14 inches
of water. If you do not reduce incoming gas pres-
sure, heater regulator damage could occur. Install
external regulator with the vent pointing down
INSTALLATION
Continued
as shown in Figure 13. Pointing the vent down
protects it from freezing rain or sleet.
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 1/2" diameter or
greater to allow proper gas volume
to heater. If pipe is too small, undue
loss of volume will occur.
Installation must include an 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, page 14).
IMPORTANT: Install equipment shutoff valve in an
accessible location. The equipment shutoff valve is for
turning on or shutting off the gas to the appliance.
Check your building codes for any special
requirements for locating equipment shutoff
valve to fireplaces.
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.
WARNING: Use pipe joint
sealant that is resistant to liquid
petroleum (LP) gas.
We recommend that you install a sediment trap in
supply line as shown in Figures 14, page 14. Locate
sediment trap where it is within reach for clean-
ing. Install in piping system between fuel supply
and heater. 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.
Propane/LP
Supply Tank
External
Regulator
Figure 13 - External Regulator With Vent
Pointing Down
Vent
Pointing
Down

www.desatech.com 111347-01E
14
CAUTION: Make sure exter-
nal regulator has been installed
between propane/LP supply
and heater. See guidelines un-
der Connecting to Gas Supply,
page 13.
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 (control valve) and equipment 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 equipment
shutoff valve was connected.
3. Pressurize supply piping system by either
opening propane/LP supply tank valve for
propane/LP gas or opening main gas valve
located on or near gas meter for natural gas
or using compressed air.
4. Check all joints of gas supply piping system.
Apply 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 fit-
tings for leaks.
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 supply tank valve for
propane/LP gas or opening main gas valve
located on or near gas meter for natural gas
or using compressed air.
3. Check all joints from gas meter to equipment
shutoff valve for natural gas or propane/LP sup-
ply to equipment shutoff valve for propane/LP
(see Figures 16 and 17, page 15). Apply noncor-
rosive leak detection fluid to all joints. Bubbles
forming show a leak.
4. Correct all leaks at once.
CAUTION: Avoid damage to
regulator. Hold gas regulator
with wrench when connecting it
to gas piping and/or fittings.
INSTALLATION
Continued
Tee Pipe Cap
Joint Nipple
PROPANE/LP
From External
Regulator (11" W.C.**
to 14" W.C. Pressure)
NATURAL
From Gas Meter
(5" W.C.** to
10.5" W.C.
Pressure)
Sediment Trap
3" Minimum
CSA Design-Certified
Equipment Shutoff Valve
With 1/8" NPT Tap*
Approved Flexible
Gas Hose (if allowed
by local codes)
Gas
Regulator
Figure 14 - Gas Connection
* Purchase the optional CSA design-certified
equipment shutoff valve from your dealer. See
Accessories, page 27.
** Minimum inlet pressure for purpose of input
adjustment.
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 use an open
flame to check for a leak. Apply
a noncorrosive leak detection
fluid to all joints. Bubbles form-
ing show a leak. Correct all leaks
at once.
Figure 15 - Equipment Shutoff Valve
Equipment
Shutoff
Valve
Open
Closed

www.desatech.com
111347-01E 15
PRESSURE TESTING HEATER GAS
CONNECTIONS
1. Open equipment shutoff valve (see Figure 15,
page 14).
2. Open main gas valve located on or near gas
meter for natural gas or open propane/LP
supply tank valve.
3. Make sure control knob of heater is in the OFF
position.
4. Check all joints from equipment shutoff valve
to control valve (see Figures 16 and 17). Apply
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 16)
depending on your model). Check all other
internal joints for leaks.
7. Turn off heater (see To Turn Off Gas to Ap-
pliance, page 18 or 20, depending on your
model).
INSTALLATION
Continued
Figure 16 - Checking Gas Joints
(Propane/LP only)
Gas Control
Valve Location
Propane/LP
Supply Tank
Equipment
Shutoff Valve
Figure 17 - Checking Gas Joints (Natural
Gas Only)
Gas Meter
Gas Control
Valve Location Equipment
Shutoff Valve
Figure 18 - Rear Log Placement (Variable
Manually-Controlled Models)
Rear Log
INSTALLING LOGS
WARNING: Failure to position
the parts in accordance with these
diagrams or failure to use only
parts specifically approved with
this heater may result in property
damage or personal injury.
CAUTION: After installation
and periodically thereafter,
check to ensure that no flame
comes in contact with any log.
With the heater set to HI, check
to see if flames contact any log. If
so, reposition logs according to
the log installation instructions
in this manual. Flames contact-
ing logs will create soot.
It is very important to install the logs exactly as
instructed. Do not modify logs. Only use logs
supplied with heater.
Variable Manually-Controlled Models
(LSL)
1. Place rear log onto rear brackets making sure
brackets fit into recess on bottom of log (see
Figure 18).
2. Place left front log on grate fingers as shown
in Figure 19, page 16. Place right front log on
grate fingers and on left front log (see Figure
19, page 16).
3. Slide control cover log into position between
two front logs assuring the cover log seats into
cutout section (see Figure 20, page 16).

www.desatech.com 111347-01E
16
INSTALLATION
Continued
Figure 19 - Left and Right Front Log
Placement (Variable Manually-Controlled
Models)
Figure 20 - Control Cover Log Placement
(Variable Manually-Controlled Models)
Left Front
Log
Right
Front Log
Cover Log
Crossover
Log
Thermostat Models (CDL)
1. Place rear log on 2 pins on rear brackets (see
Figure 21).
2. Place front log on grate fingers and over pins
of rear log as shown in see Figure 21.
3. Place control cover log onto two pins on front
log assuring the cover log seats into cutout
section of front log (see Figure 22).
4. Place crossover log on pins on rear and middle
log (see Figure 22).
Figure 21 - Front and Rear Log
Placement (Thermostat Models)
Figure 22 - Front Log Placement
(Thermostat Models)
Rear and
Middle Log
Front Log
Cover
Log
Crossover
Log
OPERATING HEATER
MANUALLY-CONTROLLED
MODELS
FOR YOUR SAFETY
READ BEFORE LIGHTING
WARNING: If you do not follow
these instructions exactly, a fire
or explosion may result caus-
ing property damage, personal
injury or loss of life.
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 neighborʼs phone. Follow the
gas supplierʼs 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, donʼt
try to repair it, call a qualified service tech-
nician 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.

www.desatech.com
111347-01E 17
LIGHTING
INSTRUCTIONS
WARNING:
• If fireplace has glass doors,
never operate this heater with
glass doors closed. If you op-
erate heater with doors closed,
heat buildup inside fireplace
will cause glass to burst. Make
sure there are no obstructions
across opening of fireplace.
• You must operate this heater
with a fireplace screen in place.
Make sure fireplace screen is
closed before running heater.
NOTICE: During initial operation
of new heater, burning logs will
give off a paper-burning smell.
Orange flame will also be pres-
ent. Open damper or window to
vent smell. This will only last a
few hours.
Note: Home owners generally prefer to operate
their heater with the chimney damper closed.
This will put all the heat into the room. How-
ever, there may be times you will desire the full
flames of the HI heat setting but will find the
heat output excessive. You can open the chim-
ney damper (if you have one) fully or partially
to release some of the heat.
WARNING: Damper handle will
be hot if heater has been running.
1. STOP! Read the safety information on
page 16.
2. Remove control cover log (see Figure 23).
3. Make sure equipment shutoff valve is fully
open.
4. Press in and turn control knob clockwise
to the OFF position.
5. 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, page 16. If you donʼt
smell gas, go to the next step.
6. Slightly depress and turn control knob
counterclockwise to the PILOT
position. Keep control knob pressed in for
five (5) seconds (see Figure 23).
Note: You may be running this heater for
the first time after hooking up to gas sup-
ply. If so, the control knob may need to be
pressed in for 30 seconds or more. This will
allow air to bleed from the gas system.
7. With control knob pressed in, press and
release ignitor button. This will light pilot.
The pilot is attached to the burner. If needed,
keep pressing ignitor button until pilot
lights. Note: If pilot does not light, 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 18.
8. Keep control knob pressed in for 30 seconds
after lighting pilot. After 30 seconds, release
control knob.
• If control knob does not pop out when
released, contact a qualified service
person or gas supplier for repairs.
Note: If pilot goes out, repeat steps 3
through 7.
9. Slightly depress and turn control knob
counterclockwise to the HI position.
The burner should light. Set control knob
to any heat level between HI and LO.
10. Replace control cover log (see Figure 23).
OPERATING HEATER
Continued
Figure 23 - Control Knob and Ignitor
Button Location (Actual Logs May Vary)
Control
Knob
Ignitor
Button
Control
Cover
Log
Thermocouple Ignitor Electrode
Pilot Burner
Figure 24 - Pilot
(Note: Appearance of pilot assembly may vary
by model.)

www.desatech.com 111347-01E
18
VARIABLE CONTROL
OPERATION
The variable control valve can be set to any
heat setting and flame height desired, by simply
turning the control knob until that setting is
attained. Even the lowest setting provides re-
alistic, dancing yellow flames. Selecting higher
settings produces greater heat output. This
results in increased heating comfort.
WARNING: Do not operate
heater between PILOT and HI
positions.
CAUTION: Do not try to ad-
just heating levels by using the
equipment shutoff valve.
TO TURN OFF GAS
TO APPLIANCE
Shutting Off Heater
1. Remove control cover log (see Figure 23,
page 17).
2. Press in and turn control knob clockwise
to the HI position.
3. Turn the control knob clockwise to
the PILOT position.
4. Press in control knob and turn clockwise
to the OFF position.
5. Replace control cover log (see Figure 23,
page 17).
Shutting Off Burners Only (pilot stays lit)
1. Remove control cover log (see Figure 23,
page 17).
2. Turn the control knob clockwise to
the HI position.
3. Press in and turn control knob clockwise
to the PILOT position.
4. Replace control cover log (see Figure 23,
page 17).
OPERATING HEATER
Continued
MANUAL LIGHTING
PROCEDURE
1. Follow steps 1 through 6 under Lighting
Instructions, page 17.
2. Depress control knob and light pilot with
match.
3. Keep control knob pressed in for 30 seconds
after lighting pilot. After 30 seconds, release
control knob. Now follow steps 9 and 10,
page 17.
THERMOSTAT MODELS
FOR YOUR SAFETY READ
BEFORE LIGHTING
WARNING: If you do not fol-
low these instructions exactly,
a fire or explosion may result
causing property damage, per-
sonal injury or loss of life.
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 neighborʼs phone. Follow the
gas supplierʼs 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, donʼt
try to repair it, call a qualified service tech-
nician 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.

www.desatech.com
111347-01E 19
LIGHTING
INSTRUCTIONS
WARNING:
• If fireplace has glass doors,
never operate this heater with
glass doors closed. If you op-
erate heater with doors closed,
heat buildup inside fireplace
will cause glass to burst. Make
sure there are no obstructions
across opening of fireplace.
• You must operate this heater
with a fireplace screen in place.
Make sure fireplace screen is
closed before running heater.
NOTICE: During initial operation
of new heater, burning logs will
give off a paper-burning smell.
Orange flame will also be pres-
ent. Open damper or window to
vent smell. This will only last a
few hours.
Note: Home owners generally prefer to op-
erate their heater with the chimney damper
closed. This will put all the heat into the room.
However, there may be times you will desire
the full flames of the HI heat setting but will
find the heat output excessive. You can open
the chimney damper (if you have one) fully or
partially to release some of the heat.
WARNING: Damper handle
will be hot if heater has been
running.
1. STOP! Read the safety information in
column 2, page 18.
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! Follow “B” in the
safety information in column 2, page 18. If
you donʼt smell gas, go to the next step.
OPERATING HEATER
Continued
5. Turn control knob counterclockwise
to the PILOT position. Press in control
knob for five (5) seconds (see Figure 25).
Note: You may be running this heater for
the first time after hooking up to gas sup-
ply. If so, the control knob may need to be
pressed in for 30 seconds or more. This will
allow air to bleed from the gas system.
• If control knob does not pop out when
released, contact a qualified service
person or gas supplier for repairs.
6. With control knob pressed in, press and
release ignitor button. This will light pilot.
The pilot is attached to the front burner. If
needed, keep pressing ignitor button until
pilot lights.
Note: If pilot does not stay lit, 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 20.
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. This heater has a safety interlock
system. Wait one (1) minute for system to
reset before lighting pilot again.
8. Turn control knob counterclockwise
to desired heating level. The burners should
light. Set control knob to any heat level
between HI and LO.
CAUTION: Do not try to ad-
just heating levels by using the
equipment shutoff valve.
LO
HI
OFF
Pilot
Figure 25 - Control Knob and Ignitor
Button Location
Control Knob
Ignitor
Button
Figure 26 - Pilot
Thermocouple
Ignitor Electrode
Pilot Burner

www.desatech.com 111347-01E
20
OPERATING HEATER
Continued
TO TURN OFF GAS
TO APPLIANCE
Shutting Off Heater
Turn control knob clockwise to the
OFF position.
Shutting Off Burners Only (pilot stays lit)
Turn control knob clockwise to the
PILOT position.
THERMOSTAT
CONTROL OPERATION
The thermostat control knob can be set to any
comfort level between HI and LO. The ther-
mostat will gradually modulate the heat output
and flame height from higher to lower settings
or pilot, in order to maintain the comfort level
you select. The ideal comfort setting will vary
by household depending upon the amount of
space to be heated, the output of the central
heating system, etc.
Note: Selecting the HI setting with the control
knob will cause the burners to remain fully on,
without modulating down in most cases.
MANUAL LIGHTING
PROCEDURE
1. Follow steps 1 through 5 under Lighting
Instructions, page 19.
2. Depress control knob and light pilot with
match.
3. 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 19.
INSPECTING BURNERS
Check pilot flame pattern and burner flame pat-
terns often.
PILOT FLAME PATTERN
Figure 27 shows a correct pilot flame pattern. Figure
28 shows an incorrect pilot flame pattern. The incor-
rect 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 28
• turn heater off (see To Turn Off Gas to Appliance,
page 18 [Manually-Controlled Models] or page
20 [Thermostatically-Controlled Models])
• see Troubleshooting, page 22
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 27 - Correct Pilot Flame Pattern
(Your pilot may vary from pilots shown)
Pilot Burner
Thermocouple
Pilot Burner
Thermocouple
Figure 28 - Incorrect Pilot Flame Pattern
(Your pilot may vary from pilots shown)
BURNER PRIMARY AIR HOLES
Air is drawn into the burner through the holes in
the fitting at the burner entrance. These holes may
become blocked with dust or lint. Periodically
inspect these holes for any blockage and clean if
needed. Blocked air holes will create soot.
MAIN BURNER
Periodically inspect all burner flame holes with the
heater running. All slotted burner flame holes should
be open with yellow flame present. All round burner
flame holes should be open with a small blue flame
present. Some burner flame holes may become
blocked by debris or rust, with no flame present. If
so, turn off heater and let cool. Remove blockage.
Blocked burner flame holes will create soot.