Desa VRL24NR Operation manual

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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.
Patent Pending
UNVENTED (VENT-FREE) GAS LOG HEATER
OWNER’S OPERATION AND INSTALLATION MANUAL
24" AND 30" REMOTE-READY MODELS:
VRL24NR, VRL24PR, VRL30NR, VRL30PR, CSG3924NR,
CSG3924PR, CTB3924NR, CTB3924PR, CSG3930NR, CSG3930PR
24" AND 30" THERMOSTAT MODELS:
VRL24NT, VRL24PT, VRL30NT, VRL30PT, CSG3924NT, CSG3924PT,
CTB3924NT, CTB3924PT
Remote-Ready Models Also Design-Certified As Vented Decorative Appliances

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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
stating 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 6 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
Product Identification ........................................... 5
Optional Remote Control Accessories ................. 5
Local Codes ........................................................ 5
Unpacking ........................................................... 6
Product Features ................................................. 6
Air For Combustion and Ventilation ..................... 6
Installation ........................................................... 8
Operating Heater ............................................... 20
Inspecting Burners ............................................ 25
Cleaning and Maintenance ................................ 26
Troubleshooting ................................................. 28
Optional Positioning of Thermostat Sensing Bulb .. 32
Wiring Diagram .................................................. 33
Specifications .................................................... 34
Illustrated Parts Breakdown .............................. 35
Replacement Parts ............................................ 40
Technical Service .............................................. 40
Service Hints ..................................................... 40
Accessories ....................................................... 41

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110021-01H 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, op-
erate or service this fireplace.
Improper use of this fireplace
can cause serious injury or
death from burns, fire, explo-
sion, 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
headaches, dizziness or nausea. If you have these
signs, the fireplace may not be working properly.
Get fresh air at once! Have fireplace 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 propane/
LP gases are odorless. An odor-making agent is
added to these gases. 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 warnings.
Keep this manual for reference. It is your guide to
safe and proper operation of this fireplace.
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: This appliance is
for installation only in a solid-fuel
burning fireplace or approved
ventless firebox enclosure.
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.
Carefully supervise young chil-
dren when they are in the room
with heater. When using the hand-
held remote accessory, keep se-
lector switch in the OFF position
to prevent children from turning
on burners with remote.
You must operate this heater
with a fireplace screen in place.
Make sure fireplace screen is
closed before running heater.

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SAFETY INFORMATION
Continued
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 or furniture.
10. This heater needs fresh, outside air ventilation
to run properly. This heater has an Oxygen De-
pletion Sensing (ODS) safety shutoff system.
The ODS shuts down the heater if not enough
fresh air is available. See Air for Combustion
and Ventilation, page 6. If heater keeps shutting
off, see Troubleshooting, page 28.
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. Make sure the selector
switch is in the OFF position (Remote-Ready
Models Only). Only a qualified service person
should install, service or repair heater.
16. Make sure the selector switch is in the OFF
position when you are away from home for long
periods of time (Remote-Ready Models Only).
17. Remote-ready heaters do not need to be con-
nected to any external electrical source.
18. Operating heater above elevations of 4,500
feet could cause pilot outage.
19. To prevent performance problems with pro-
pane/LP models, do not use propane/LP fuel
tank of less than 100 lb. capacity.
20. Provide adequate clearances around air
openings.
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).
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 13 (Remote-Ready
Models only).
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. A dirty chimney
flue may create and distribute soot within
the house. Inspect chimney flue and firebox
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 fire-
place will cause glass to burst. Make sure there are
no obstructions across openings of fireplace.
8. To prevent the creation of soot, follow the
instructions in Cleaning and Maintenance,
page 26.

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110021-01H 5
OPTIONAL REMOTE
CONTROL ACCESSORIES
There are four optional remote controls that
can be purchased separately for Remote-Ready
Models Only:
• wall switch • hand-held ON/OFF remote
• wall thermostat • hand-held thermostat remote
See Accessories, page 41.
The wall thermostat or hand-held thermostat
may not be used where vented decorative listing
is required.
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/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 models are not permitted.
PRODUCT
IDENTIFICATION
Base
Assembly
Piezo
Ignitor
Front and Rear
Burner Control
Knob
Selector Switch
(Optional)
ON/OFF/
PILOT
Knob
Remote Control
(Optional)
Grate
Front
Burner
Remote-Ready Models
Rear
Burner
Figure 1 - Product Identification
Log Set (Varies
According to Model)
Base
Assembly
Front and Rear
Burner Control Knob
Piezo
Ignitor
Burner
Control
Knob
Thermostat Models
Grate
Pilot
Assembly
Middle
Burner
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.

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6
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 the sides of
assembly.
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.
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 both realistic flames
and glowing coals. 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
(Remote-Ready Models Only).
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.
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 con-
struction unless provisions are
provided for adequate combus-
tion 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 6 through 8 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.

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110021-01H 7
AIR FOR COMBUSTION
AND VENTILATION
Continued
40,000
31,500
71,500
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 (6x10-11 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 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 8.
If your home does not meet all of the three
criteria above, proceed to Determining
Fresh-Air Flow For Heater Location.
Confined Space 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 FIREPLACE 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
fireplace plus any adjoining rooms with doorless pas-
sageways 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) = 2,560 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: 2,560 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 fireplace __________ 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)
79,000 Btu/Hr (actual amount of
Btu/Hr used)
The space in the 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 ad-
ditional fresh air. Your options are as follows:
A. Rework worksheet, adding the space of an adjoin-
ing 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 8.
B. Vent room directly to the outdoors. See Ventila-
tion Air From Outdoors, page 8.
C. Install a lower Btu/Hr fireplace, if lower Btu/Hr
size makes room unconfined.

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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.
AIR FOR COMBUSTION
AND VENTILATION
Continued
Figure 2 - Ventilation Air from Inside
Building
Figure 3 - Ventilation Air from Outdoors
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"
If the actual Btu/Hr used is less than the maximum
Btu/Hr the space can support, the space is an un-
confined space. You will need no additional fresh
air ventilation.
WARNING: If the area in
which the heater may be oper-
ated 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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110021-01H 9
WARNING: Installation and
repair should be done by a quali-
fied service person. The appliance
should be inspected before use and
at least annually by a professional
service person. More frequent
cleaning may be required due to
excessive lint from carpeting, bed-
ding material, etc. It is imperative
that control compartments, burners
and circulating air passageways of
the appliance be kept clean.
NOTICE: State or local codes may
only allow operation of this appli-
ance in a vented configuration.
Check your state or local codes
(Remote-Ready Models Only).
WARNING: Make sure the
selector switch is in the OFF
position before installing heater
(Remote-Ready Models Only).
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. Creo-
sote will ignite if highly heated. A
dirty chimney flue may create and
distribute soot within the house.
Inspect chimney flue and firebox
for damage. If damaged, repair
flue before operating heater.
WARNING: Seal any fresh
air vents or ash clean-out doors
located on floor or wall of fire-
place. If not, drafting may cause
pilot outage or sooting. Use a
heat-resistant sealant. Do not
seal chimney flue damper.
INSTALLATION
Continued WARNING: Never install the
heater
• in a bedroom or bathroom
unless installed as a vented
appliance, see page 13 (Re-
mote-Ready Models Only)
• 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 firebox opening
• 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 6.
CHECK GAS TYPE
Use only the correct gas type (natural or pro-
pane/LP) for your unit. If your gas supply is not
correct, do not install heater. Call dealer where
you bought heater for proper type heater.
WARNING: This appliance
is equipped for (natural or pro-
pane/LP) gas. Field conversion
is not permitted.

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10
LOG SIZING REQUIREMENTS
Minimum Firebox Size
Log Front Rear
Size Height Depth Width Width*
24" 17" 14" 28" 20 1/4"
30" 17" 14" 34" 22 3/8"
*Measured at 14" Depth
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 13.
Minimum Noncombustible Material
Clearances
If Not Using Mantel
Note: If using a mantel, proceed to If Using
Mantel below. If not using a mantel, follow the
information below.
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. Noncom-
bustible material must extend at least 8" up. If
noncombustible material is less than 12", you must
install the fireplace hood accessory. See Figure 5,
page 11, 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 13.
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. Noncombustible
material must extend at least 8 inches up (for all
models). If noncombustible material is less than
12", you must install the fireplace hood accessory
(24" model only). 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 and 6, page 11 and Figure 7 page 12,
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 13.
INSTALLATION AND CLEARANCES
(Vent-Free Operation Only)
WARNING: Maintain the
minimum clearances. If you can,
provide greater clearances from
floor, ceiling and adjoining wall.
INSTALLATION
Continued
Carefully follow the instructions below. This will
ensure safe installation into a masonry, UL127-
listed manufactured fireplace or certified 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.

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110021-01H 11
Noncombustible Requirements for
Material Distance (A) Safe Installation
12" or more Noncombustible material okay.
Between 8" Install fireplace hood and 12"
accessory (GA6050, GA6052 or
GA6053, see Accessories, page 41).
Less than 8" Noncombustible material 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
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).
Figure 5 - Heat Resistant Material (Slate, Marble, Tile, etc.) Above Fireplace
Figure 6 - Minimum Mantel Clearances Without Using Hood
Minimum Non-
Combustible
Material
Minimum Non-
Combustible
Material Height
Distances to
Underside of
Mantel
Top of Fireplace
Opening
Underside of
Mantel Shelf
Mantel Shelf
12"
(A)
18"
20"
22"
24"
All minimum
distances are
in inches
Log Set
All Models
2 1/2"
6"
8"
10"

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12
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
INSTALLATION
Continued
Determining Minimum Mantel Clearance
when Using a Hood
If minimum clearances in Figure 6 (page 11) 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 a hood.
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.
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).
Hearth
5"
Min.
Combustible
Material
14"
Min.
Combustible
Material
Noncombustible Material
Figure 8 - Minimum Fireplace Clearances
If Installed at Floor Level
Figure 9 - Minimum Fireplace Clearances
Above Combustible Flooring
Figure 7 - Minimum Mantel Clearances When Using Hood

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110021-01H 13
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
Chimney Minimum Permanent
Height (ft.) Flue Opening (sq. ins.)
6' to 15' 39 sq. inches
15' to 30' 29 sq. inches
Figure 10 - Attaching Damper Clamp
Manufactured
Fireplace
Masonry Fireplace
Damper
Damper
Clamp
Damper
Damper
INSTALLING DAMPER CLAMP
ACCESSORY FOR VENTED
OPERATION (Remote-Ready Models Only)
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 reasons for operating your heater in the
vented mode.
1. The fireplace does not meet the clearance
to combustibles 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 41). 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.
INSTALLATION
Continued
INSTALLING HEATER BASE
ASSEMBLY
CAUTION: Do not remove the
data plates attached to the heater
base assembly. The data plates
contain important warranty and
safety information.
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 in-
sure adequate air flow and guard
against sooting and controls be-
ing damaged. Raise fireplace floor
with noncombustible material.
Make sure material is secure.
CAUTION: Do not pick up
heater base assembly by the
burner. This could damage
heater. Only handle base as-
sembly by grates.

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14
INSTALLATION
Continued
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 32.
Installation Items Needed
• hardware package (provided with heater)
• approved flexible gas hose (not provided) (if
allowed by local codes)
• sealant (resistant to propane/LP gas, not provided)
• electric drill with 3/16" drill bit
• flathead screwdriver
1. Connect fitting to base as shown in Figure 11.
Connect approved flexible gas hose to fitting
in base (see Figure 11).
IMPORTANT: Hold gas fitting 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 18).
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 mounting bracket (see Figure 12).
If installing in a brick-bottom fireplace, mark
screw locations in mortar joint of bricks.
8. Remove heater base from fireplace. If installing
optional control accessories, do so at this time.
Follow all directions provided with accessory.
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).
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
propane/LP heater directly to the
propane/LP supply. Propane/LP
heaters require an external regu-
lator (not supplied). Install the
external regulator between the
heater and propane/LP supply.
WARNING: For natural gas
units, never connect heater to
private (non-utility) gas wells.
This gas is commonly known
as wellhead gas.
Figure 11 - Attaching Flexible Gas Hose
to Heater
Fitting
Flexible Gas Hose
(if allowed by local
codes)
Figure 12 - Attaching Base Assembly to
Fireplace Floor (30" Model Shown)
Masonry Screw
Mounting
Flange

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110021-01H 15
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 41.
For propane/LP gas, 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
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
Continued
Figure 13 - External Regulator With Vent
Pointing Down
Installation must include a 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 or 15, page
16, depending on your model).
IMPORTANT: Install equipment shutoff valve in an
accessible location. The main gas valve is for turn-
ing on or shutting off the gas to the appliance.
Check your building codes for any special re-
quirements 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 sediment trap
in supply line as shown in Figure 14 or 15, page
16, depending on your model. Locate sediment
trap where it is within reach for cleaning. 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.
CAUTION: Avoid damage to
regulator. Hold gas regulator with
wrench when connecting it to gas
piping and/or fittings (Thermo-
stat-Controlled Models Only).
CAUTION: Avoid damage to
gas control. Hold gas control
with wrench when connecting
it to gas piping and/or fittings
(Remote-Ready Models Only).
Propane/LP
Supply Tank
External
Regulator
Vent
Pointing
Down

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16
INSTALLATION
Continued
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 commercial leak de-
tection solution to all joints.
Bubbles forming show a leak.
Correct all leaks at once.
CAUTION: For propane/LP
units, make sure external regula-
tor has been installed between
propane/LP supply and heater.
See guidelines under 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. Pressures in ex-
cess 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 a commercial leak detection solution
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.
* Purchase the optional CSA design-certified
equipment shutoff valve from your dealer. See
Accessories, page 41.
** Minimum inlet pressure for purpose of input
adjustment.
Figure 15 - Gas Connection (Remote-
Ready Models Only)
Gas Control Valve
Tee Pipe Cap
Joint Nipple
3" Minimum
Sediment Trap
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)
CSA Design-Certified
Equipment Shutoff Valve
With 1/8" NPT Tap*
Approved
Flexible Gas
Hose (if allowed
by local codes)
Figure 14 - Gas Connection
Cap Pipe Tee
Nipple Joint
3" Min.
Sediment Trap
Gas
Regulator
CSA Design-Certified
Equipment Shutoff Valve
With 1/8" NPT Tap*
Approved Flexible Gas
Hose (if allowed by
local codes)
Natural 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

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110021-01H 17
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 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 for natural gas
or propane/LP supply to equipment shutoff
valve (see Figure 17 or 18). Apply a com-
mercial leak detection solution to all joints.
Bubbles forming show a leak.
4. Correct all leaks at once.
Pressure Testing Heater Gas
Connections
1. Open equipment shutoff valve (see Figure 16).
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 thermostat gas valve (Thermostat-
Controlled Models) or control valve (Remote-
Ready Models) (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 20).
Check all other internal joints for leaks.
7. Turn off heater (see To Turn Off Gas to Ap-
pliance, page 21 [thermostatically-controlled
models] or page 24 [remote-ready models]).
Figure 16 - Equipment Shutoff Valve
Equipment
Shutoff Valve
Propane/LP
Supply
Tank
Thermostat Gas
Valve or Control
Valve Location
Figure 18 - Checking Gas Joints
(Natural Gas Only)
Gas Meter
Equipment
Shutoff Valve
Figure 17 - Checking Gas Joints
(Propane/LP Gas Only)
Open
Closed
Equipment
Shutoff Valve
INSTALLATION
Continued
Thermostat Gas
Valve or Control
Valve Location

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18
INSTALLATION
Continued
INSTALLING LOGS
WARNING: Failure to posi-
tion 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 installa-
tion and periodically thereafter,
check to ensure that no flame
comes in contact with any log.
With the heater set to High, 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 sup-
plied with heater. Before installing logs, make sure
log alignment screws are in place and straight.
Models CSG3924NT, CSG3924PT,
CSG3924NR, CSG3924PR, CTB3924NT,
CTB3924PT, CTB3924NR CTB3924PR,
CSG3930NR and CSG3930PR,
1. Place log #1 (ember bed) onto base over align-
ment screws to left of front burner and behind
middle burner. Log #1 will sit on top of front
and middle burners (see Figure 19).
2. Place log #2 to the right of log #1. Log #2 will
wrap around right end of rear burner and sit
on log alignment screw (see Figure 20).
3. Place log #3 on left side of base and onto
alignment screw to right of rear burner (see
Figure 20). Log #3 will wrap around left end
of rear burner.
4. Place log #4 onto two alignment screws to the
rear of base (see Figure 21).
Figure 19 - Installing Log #1 (Ember Bed)
(Model CSG3924NR Shown)
Log #1
Log #5 will
seat in this
location.
Figure 20 - Installing Log #2 (Right) and
Log #3 (Left) (Model CSG3924NR Shown)
Figure 21 - Installing Log #4 (Model
CSG3924NR Shown)
Log #4
Log #3
Log #1
Log #2
Log #3
Log #1
Log #2

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110021-01H 19
INSTALLATION
Continued
Figure 22 - Installing Log #5 (Right) and
Log #6 (Left) (Model CSG3924NR Shown)
Log #5
Log #6
Log #4
Log #3
Log #1
Log #2
5. Place back of log #5 on notch in log #4 (as
shown in Figure 22), across back part of log
#1 and onto pin on log #2 (see Figure 20, page
18 and Figure 22).
6. Place log #6 onto two pins on log #1 (ember
bed) and rest back of log #6 on back log #4
(see Figure 22).
Figure 23 - Installing Log #2 (Right) and
Log #3 (Left) (Model VRL30NR Shown)
Figure 24 - Installing Log #4 (Model
VRL30NR Shown)
Figure 25 - Installing Log #5 and Log #6
(Model VRL30NR Shown)
Log #6
Log #5
Log #2
Log #4
Log #3
Log #1
Log #2
Log #3
Log #1
Log #4
Log #2
Log #3
Log #1
Models VRL24NR, VRL24PR, VRL30NR,
VRL30PR, VRL24NT, VRL24PT, VRL30NT
and VRL30PT
1. Place log #1 (ember bed) onto base over log
alignment screws to the left of front burner
and behind middle burner. Log #1 will sit on
top of front and middle burners (see Figure
19, page 18).
2. Place log #2 to right of log #1 and onto log
alignment screw as shown in Figure 23. Log
#2 will wrap around right end of rear burner
(see Figure 23).
3. Place log #3 on left side of base and onto
alignment screw to right of rear burner (see
Figure 23). Log #3 will wrap around left end
of rear burner.
4. Place log #4 onto two alignment screws to rear
of base (see Figure 24).
5. Locate hole on bottom of log #5 and place over
pin on log #2. Log #5 will rest on back of log
#1 (ember bed). See Figure 19, page 18 and
Figure 25.
6. Place log #6 onto two pins on log #1 (ember
bed) and rest back of log #6 on back log #4
(see Figure 25).

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20
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.
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 openings of fireplace.
• You must operate this heater
with a fireplace screen in
place. Make sure fireplace
screen is closed before run-
ning 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.
OPERATING HEATER
THERMOSTAT-CONTROLLED
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.
Figure 26 - Attaching Grate to Base
Assembly (Logs and Base Will Vary
According to Model)
Grate
Slots in Base
ATTACHING GRATE TO BASE
ASSEMBLY
Locate the two slots in the front of the base as-
sembly. Carefully slide the decorative grate into
these slots (see Figure 26).
ADDING LAVA ROCK
Place lava rock around base of heater if desired.
Be sure not to cover the control knobs or air inlet
openings on the front of heater.
INSTALLATION
Continued