Desa Comfort Glow CGFB32CA Original instructions

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.
Carefully review the instructions supplied with the
decorative type unvented room heater for the minimum
fireplace size requirement.
Do not install an appliance in this firebox unless this
firebox meets the minimum dimensions required for
the installation.
This firebox has been tested and approved by CSA
under ANSI Z21.91 for use with any ANSI Z21.11.2 ap-
proved gas logs.
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
Save this manual for future reference.
For more information, visit www.desatech.com
UNVENTED (VENT-FREE) UNIVERSAL FIREBOX
SAFETY INFORMATION AND INSTALLATION MANUAL
Shown with optional
cabinet mantel, hearth
base.
CGFB32CA
CIRCULATING LOUVERED MODEL

www.desatech.com 107331-01H2
IMPORTANT: Read this owner’s
manual carefully and completely
before trying to assemble, operate
or service this firebox. Improper
use of this firebox can cause se-
rious injury or death from burns,
fire, explosion, electrical shock or
carbon monoxide poisoning.
WARNING: Any change to
this firebox or its controls can
be dangerous.
WARNING: Do not allow fans
to blow directly into the firebox.
Avoid any drafts that alter burner
flame patterns. Ceiling fans can
create drafts that alter burner
flame patterns. Altered burner
patterns can cause sooting.
WARNING: Do not use a blow-
er insert, hood, heat exchanger
insert or other accessory not ap-
proved for use with this heater.
Due to high temperatures, the
firebox should be located out of
traffic and away from furniture
and draperies.
Firebox front and screen be-
come very hot when running
firebox. Keep children and
adults away from hot surfaces to
avoid burns or clothing ignition.
Firebox will remain hot for a time
after shutdown. Allow surfaces
to cool before touching.
SAFETY INFORMATION
TABLE OF CONTENTS
Safety Information ............................................... 2
Local Codes ........................................................ 3
Unpacking ........................................................... 3
Product Features ................................................. 3
Product Specifications ......................................... 4
Locating Firebox ................................................. 4
Air For Combustion and Ventilation ..................... 4
Installation ........................................................... 7
Technical Service .............................................. 12
Replacement Parts ............................................ 12
Accessories ....................................................... 12
Parts Centrals .................................................... 13
Illustrated Parts Breakdown and Parts List ....... 14
Warranty Information ...........................Back Cover
WARNING: Improper installation, adjustment, alteration, ser-
vice or maintenance can cause injury or property damage.
Refer to this manual for correct installation and operational
procedures. For assistance or additional information consult
a qualified installer, service agency or the gas supplier.
WARNING: For use only with a listed gas-fired unvented
decorative room heater. Not to exceed 40,000 Btu/Hr. Do not
build a wood fire.
State of Massachusetts: The installation 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 Common-
wealth of Massachusetts.

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107331-01H 3
Do not place clothing or other
flammable material on or near
firebox. Never place any objects
on the firebox or logs.
Carefully supervise young chil-
dren when they are in the room
with firebox.
You must operate this fireplace
with the provided fireplace screen
(closed), hood and brick liner in
place. Make sure these parts are
in place before running firebox.
Keep the firebox area clear and
free from combustible materials,
gasoline and other flammable
vapors and liquids.
1. This firebox shall not be installed in a bedroom
or bathroom.
2. Never install the firebox
• 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
• in high traffic areas
• in windy or drafty areas
3. Do not use this firebox as a wood-burning
fireplace. Use only decorative unvented room
heaters (log sets).
4. Do not add extra logs or ornaments such as pine
cones, vermiculite or rock wool. Using these
added items can cause sooting.
5. Vent-free gas log heaters installed in these fire-
boxes require fresh air ventilation to run properly.
See Air for Combustion and Ventilation, page 4.
6. Do not run firebox
• where flammable liquids or vapors are used
or stored
• under dusty conditions
7. Do not use this firebox to cook food or burn paper
or other objects.
8. Turn firebox off and let cool before servicing.
Only a qualified service person should service
and repair firebox.
9. Operating vent-free log sets in a firebox above
elevations of 4,500 feet could cause pilot outage.
SAFETY INFORMATION
Continued
10.
Do not use the firebox if it has been under water
due to the shock hazard that could result with
the blower accessary (if installed) in place.
11. Provide adequate clearances around air
openings.
LOCAL CODES
Install and use fireplace with care. Follow all local
codes. In the absence of local codes, use the latest edi-
tion of The National Fuel Gas Code ANSI Z223.1/
NFPA 54*. Firebox must be electrically grounded
in accordance with the National Electrical Code,
ANSI/NFPA70 (latest edition).
*Available from:
American National Standards Institute, Inc.
1430 Broadway
New York, NY 10018
National Fire Protection Association, Inc.
Batterymarch Park
Quincy, MA 02269
UNPACKING
1. With utility knife, cut the carton all the way
around above the staples on the bottom tray. Lift
the carton off the firebox. Remove packing.
2. Check carton contents for the following:
• Screen assembly
• Screen support rod
• Hardware and parts bag containing the fol-
lowing:
- Ownerʼs Operation and Installation Manual
- 2 - Black #10 x 3/8" Phillips screws
3. If any items are missing, inform dealer where
you bought the firebox.
4. Check all items for any shipping damage. If
damaged, promptly inform dealer where you
bought firebox.
PRODUCT FEATURES
OPERATION
This firebox is designed to accept unvented
decorative gas logs. It requires no outside vent-
ing or chimney making installation easy and
inexpensive. When used without the blower the
firebox requires no electricity making it ideal for
emergency backup heat.
BLOWER ACCESSORY
The CGFB32CA firebox will accept the GA3750A
accessory. The variable blower allows you to select
the fan speed you desire. The blower circulates
heated air from the firebox into the room. Use of
blower is optional.

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PRODUCT
SPECIFICATIONS
22 1/2"16 11/16"
13 1/4"
*
14
1/4"31 5/8"
34 3/8"
35 5/8"19 1/4"
Figure 3 - Firebox Top View
*Note: 141/4" is total firebox cavity depth including
brick liner. 131/4" is depth of flat floor including
brick liner.
LOCATING FIREBOX
Plan where you will install the firebox. This will
save time and money later when you install the fire-
box. Before installation, consider the following:
1. Where the firebox will be located. Allow for
wall and ceiling clearances (see Installation
Clearances, page 7).
2. Everything needed to complete installation.
3. These models CANNOT be installed in a
bedroom or bathroom.
4. Proper air for combustion and ventilation (see
Air For Combustion and Ventilation).
AIR FOR COMBUSTION
AND VENTILATION
WARNING: This firebox shall
not be installed in a confined
space or unusually tight construc-
tion unless provisions are provid-
ed 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, fireboxes, 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
12
1
/
2
"9
3
/
4
"4
5
/
8
"2
1
/
2
"6"32
3
/
16
"33
11
/
16
"2
1
/
4
"
Electrical Access Hole Gas Line Access
Figure 2 - Firebox Side View
35 1/16"31 3/4"1 1/4"16 1/4"2 3/4"3 7/8"
6
3
/
4
"2
3
/
4
"6
3
/
8
"19
3
/
8
"1 1/4"
Built-in Nailing Flanges
Figure 1 - Firebox Front View

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107331-01H 5
The information on pages 4 through 6 will help
you classify your space and provide adequate
ventilation.
Unusually Tight Construction
The air that leaks around doors and windows may
provide enough fresh air for combustion and ventila-
tion. However, in buildings of unusually tight con-
struction, 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 (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 6.
If your home does not meet all of the three
criteria above, proceed to Determining
Fresh-Air Flow For Firebox 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.
AIR FOR COMBUSTION
AND VENTILATION
Continued
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)
79,000 Btu/Hr (actual amount of
Btu/Hr used)
40,000
39,000
79,000

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AIR FOR COMBUSTION
AND VENTILATION
Continued
The space in the above example is a confined space
because the actual Btu/Hr used is more than the maxi-
mum Btu/Hr the space can support. You must provide
additional fresh air. Your options are as follows:
A.
Rework worksheet, adding the space of an
adjoining room. If the extra space provides an
unconfined space, remove door to adjoining
room or add ventilation grills between rooms. See
Ventilation Air From Inside Building below.
B. Vent room directly to the outdoors. See Ven-
tilation Air From Outdoors.
C. Install a lower Btu/Hr heater, if lower Btu/Hr
size makes room unconfined.
If the actual Btu/Hr used is less than the
maximum Btu/Hr the space can support, the
space is an unconfined space. You will need
no additional fresh air ventilation.
WARNING: If the area in
which the firebox and gas log
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 4). You
can also remove door into adjoining room (see
option 3, Figure 4). 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.
Figure 4 - Ventilation Air from Inside
Building
OrRemoveDoor intoAdjoiningRoom,Option3
Ventilation Grills Into Adjoining Room,Option 2VentilationGrills Into Adjoining Room,Option 1
12"
12"
Figure 5 - Ventilation Air from Outdoors
OutletAirVentilatedAttic Outlet
A
irInletAirInlet AirVentilated Crawl SpaceTo CrawlSpace
To Attic

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107331-01H 7
Use the dimensions shown for rough openings to
create the easiest installation (see Built-In Firebox
Installation, page 11).
INSTALLATION CLEARANCES
WARNING: Maintain the
minimum clearances. If you
can, provide greater clearances
from floor, ceiling and adjoining
wall.
Carefully follow the instructions below. This will
ensure safe installation.
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 6.
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 opening (see Figure 6).
B. Clearances from the top of the fireplace opening
to the ceiling should not be less than 42 inches.
*
Example
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 ser-
vice person must install firebox.
Follow all local codes.
WARNING: Never install the
firebox
• in a bedroom or bathroom
• 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
• in high traffic areas
IMPORTANT: Vent-free gas log heaters add
moisture to the air. Although this is beneficial,
installing firebox in rooms without enough
ventilation air may cause mildew to form from
too much moisture. See Air for Combustion and
Ventilation, page 4.
IMPORTANT: Make sure the firebox is level.
If firebox is not level, log set will not work
properly.
Note: Your Comfort Glow firebox is designed to
be used in zero clearance installations. Wall or
framing material can be placed directly against any
exterior surface on the rear, sides or top of your
firebox, except where standoff spacers are inte-
grally attached. If standoff spacers are attached to
your firebox, these spacers can be placed directly
against wall or framing materials.
Figure 6 - Minimum Clearance for
Combustible to Wall
*Minimum 16 inches from Side Wall

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SuppliedFirebox HoodMust Be Usedat All TimesWire-meshScreenFireboxMantel Shelf13"
16"19"21"
2
1/2
"6"8"10"ForCGFB32CSeriescirculatinglouveredmodelsonly
Note:
A
ll vertical measurementsare from top of fireplaceopening to bottom of mantelshelf. All measurementsare in inches.Facing material (abovefirebox) may be of combustible material,including decorative mantel ornaments.
Mantel Clearances for Built-In
Installation
If placing custom mantel above built-in firebox,
you must meet the minimum allowable clearance
between mantel shelf and top of firebox opening
shown in Figure 7. These are the minimum allow-
able mantel clearances for a safe installation. Use
larger clearances wherever possible to minimize
the heating of objects and materials placed on
the mantel.
CAUTION: Close screens
before operation of vent-free
gas log heater. Do not allow the
heater to touch or extend beyond
the fireplace screen.
If your installation does not meet the minimum
clearances in Figure 7, you must:
• raise the mantel to an acceptable height,
OR
• remove the mantel.
INSTALLATION
Continued
Figure 7 - Minimum Mantel Clearances
for Built-In Installation
INSTALLING BLOWER ACCESSORY
You may install blower accessory GA3750A with
conventional installation (below) or with built-in
installation (see Built-In Installation of Blower
Accessory). To install blower accessory, see in-
struction sheet included with the kit.
Side
Opening
Support Bracket
Opening
Blower Power
Cord
Figure 8 - Routing Blower Accessory
Power Cord for Conventional Installation
Electrical
Outlet
Blower
Built-In Installation of Blower Accessory
1. Install blower assembly per instruction sheet
included.
2.
Before replacing bottom of firebox, remove screw
holding duplex outlet to the support bracket in
the bottom of firebox. Remove duplex outlet.
3. Clamp electrical cable into firebox through
smallest hole using strain relief provided.
4. Route wires from electrical box through hole
in side of heater and hole in support bracket
(see Figure 9, page 9).
5. Connect wires from the electrical box to
duplex outlet. Match wire colors to those
indicated on duplex outlet. Be sure to connect
ground wire.
Conventional Installation of Blower
Accessory
1. Install blower assembly per instruction sheet
included in blower accessory kit.
2. Before replacing bottom of firebox, route
blower power cord through hole in support
bracket in bottom of firebox and through hole
in side of firebox to grounded, three-prong
120 volt electrical outlet (see Figure 8). Plug
electrical cord into outlet.
3. Replace bottom of firebox.
NOTICE: A certified electrician
must connect electrical wiring to
duplex outlet for built-in instal-
lation. Follow all local codes. In
absence of local codes, follow
the National Electrical Code,
ANSI/NFPA 70 (Latest Edition).

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107331-01H 9
4. Route flexible gas line from equipment shutoff
valve into firebox through side.
NOTICE: Most building codes
do not permit concealed gas
connections. A flexible gas line
is recommended to allow acces-
sibility from the firebox. The flex-
ible gas supply line connection
to the equipment shutoff valve
should be accessible.
5. Attach gas log heater base to firebox bottom
with four screws included with base (see
Installing Heater Base Assembly in log set
ownerʼs manual).
6. Replace firebox bottom and secure with
screws.
INSTALLATION
Continued
Figure 9 - Routing Blower Accessory
Power Cord for Built-In Installation
Screw
Blower
Power Cord
Blower Support Bracket
Cables From
Electrical Source
Duplex
Outlet
Operating the Blower
Light your gas appliance with the blower off. After
about 15 minutes, turn the blower on to deliver
heated air at the top louvers. The blower features
a variable control which allows you to select the
speed you desire.
Note: Periodically check the louvers of the firebox
and remove any dust, dirt or other obstructions.
INSTALLING LOG HEATER IN
FIREBOX
CAUTION: Do not pick up log
base assembly by burners. This
could damage burners. Only
handle base by grates.
CAUTION: Do not remove the
data plates attached to the heater
base assembly. The data plates
contain important warranty and
safety information.
1. Remove four screws holding firebox bottom
in place.
2.
Lift and remove firebox bottom (see Figure 10).
3. If installing GA3750A blower accessory, see
Installing Blower Accessory, page 8.
Figure 10 - Removing Firebox Bottom
6. Replace duplex outlet with screw.
7. Plug blower power cord into duplex outlet.
8. Replace bottom of firebox.
Figure 11 - Installing Fireplace Hood
INSTALLING FIREPLACE HOOD
NOTICE: The firebox canopy (hood)
must not be modified or replaced
with a canopy (hood) that may be
provided with the unvented decora-
tive room heater.
1. Attach three zinc-colored shoulder screws to
back of hood.
2. Insert hood into hood-mounting slots on
firebox.
3. Hold hood in place. Insert two black Phillips
screws through bottom of hood and tighten.
Hood Hood
Mounting
Slot
Screw
Shoulder
Screw

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INSTALLATION
Continued
INSTALLING FIREPLACE SCREEN
1. Insert each rod through nine rings located at
top of screen (see Figure 12).
2. Insert first rod into rear hole in left side of
firebox. Fasten rod to rear hole near center of
firebox using black shoulder screw.
3. Insert other rod into front hole on right side of
firebox and fasten using remaining shoulder
screw.
Ring
Figure 12 - Installing Fireplace Screen
Rod
Front and
Rear Hole
Screen
Screw
FIREBOX INSTALLATION USING
OPTIONAL ACCESSORY MANTELS
This firebox may be installed using the cabinet
mantel and hearth base accessories against a wall
in your home. Follow the instructions below to
install the firebox in this manner.
Note: The instructions below show installation
using GMC11F/GMC12U/GMC13F series cabinet
mantels and the GC3333F/GC3334U/GC3335F
series hearth base accessories. The hearth base
accessory shown is optional for this installation.
You can install firebox and cabinet mantel directly
on the floor.
1.
Assemble cabinet mantel, hearth base and pe-
rimeter trim (Included with mantel). Assembly
instructions are included with each accessory.
2. If using an optional GA3750A blower, install a
properly grounded, 120 volt three-prong electri-
cal outlet at firebox location if an outlet is not
there. If possible, locate outlet so cabinet mantel
will cover it when installed (see Figure 14).
3. Install gas piping to firebox location. This
installation includes an approved flexible gas
line (if allowed by local codes) and a equip-
ment shutoff valve. The flexible gas line must
be the last item installed on the gas piping.
See Connecting to Gas Supply in your log set
ownerʼs manual.
Figure 13 - Placing Hearth Base
Accessory Against Wall
Electrical Outlet
Hearth
Base Gas Line
Access Hole
Rigid Pipe and Gas
Shutoff Valve
Figure 14 - Installing Cabinet Mantel
Cabinet
Mantel
WARNING: A qualified
service person must connect
firebox to gas supply. Follow all
local codes.
4. Place hearth base accessory against wall at
installation location. Cut an access hole in
hearth top to run flexible gas line to firebox
(see Figure 13). Make sure to locate access
hole so cabinet mantel will cover it when
installed. Note: You can secure base to floor
using wood screws. Countersink screw heads
and putty over.
5. Route flexible gas line through access hole in
hearth base.
6.
Center cabinet mantel on hearth base (see Figure
14). Make sure mantel is flush against wall.
7. Break off nailing flanges (see Figure 15, page
11) with hammer or pliers.
8. Place cardboard or other protective material
on top of hearth base. Carefully set firebox
on protective material, with back of firebox
inside mantel opening.