Desa VFF-32S-AKA Quick start guide

For more information, visit www.desatech.com
WARNING: If the information in this manual is not fol-
lowed exactly, a re or explosion may result causing
property damage, personal injury or loss of life.
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.
Carefully review the instructions supplied with the
decorative type unvented room heater for the minimum
replace size requirement.
DO NOT INSTALL THE APPLIANCE IN THIS FIREBOX,
UNLESS THIS FIREBOX MEETS THE MINIMUM DIMEN-
SIONS REQUIRED FOR THE INSTALLATION.
This rebox has been tested and approved by Omni Test
Laboratories under ANSI Z21.91 for use with any ANSI
Z21.11.2 approved gas logs.
INSTALLER: Leave this manual with the appliance.
CONSUMER: Retain this manual for future reference.
UNVENTED (VENT-FREE) UNIVERSAL FIREBOX
OWNER’S OPERATION AND INSTALLATION MANUAL
NON-CIRCULATING MODELS VFF-32S-AKA, VFF-36S-AKA,
VFF-42S-AKA, VTFB32. VTFB36 AND VTFB42

www.desatech.com 116208-01C2
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 qualied installer, service
agency or the gas supplier.
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
State of Massachusetts: The installation must be made by a licensed plumber or gas tter in the
Commonwealth of Massachusetts.
Sellers of unvented propane or natural gas-red 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.
TABLE OF CONTENTS
Safety Information ............................................... 3
Local Codes......................................................... 4
Product Features................................................. 4
Locating Firebox.................................................. 4
Product Specications......................................... 5
Air For Combustion and Ventilation ..................... 7
Installation ........................................................... 9
Replacement Parts............................................ 14
Technical Service............................................... 14
Accessories ....................................................... 14
Illustrated Parts Breakdown and Parts List........ 16
Warranty Information ...........................Back Cover

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116208-01C 3
SAFETY INFORMATION
WARNING: This product
contains and/or generates
chemicals known to the state
of California to cause cancer or
birth defects or other reproduc-
tive harm.
IMPORTANT: Read this owner’s
manual carefully and completely
before trying to assemble,
operate or service this heater.
Improper use of this replace
can cause serious injury or
death from burns, re, explo-
sion, electrical shock and carbon
monoxide poisoning.
WARNING: Any change to
this rebox or its controls can
be dangerous.
WARNING: Do not allow fans
to blow directly into the rebox.
Avoid any drafts that alter burner
ame patterns. Ceiling fans can
create drafts that alter burner
ame patterns. Altered burner
patterns can cause sooting.
WARNING: Do not use a blow-
er insert, heat exchanger insert
or other accessory not approved
for use with this rebox.
Firebox front and screen become
very hot when running heater.
Keep children and adults away
from hot surface to avoid burns
or clothing ignition. Firebox
will remain hot for a time after
shutdown. Allow surface to cool
before touching.
Do not place clothing or other
ammable material on or near
the appliance. Never place any
objects in the rebox or on
logs.
Carefully supervise young chil-
dren when they are in the room
with rebox.
You must operate this replace
with the provided fireplace
screen, hood if provided, in
place. Make sure these parts
are in place and screens are
closed before running rebox.
The supplied hood may not be
replaced with a hood which may
be provided with a log heater.
Keep the replace area clear and
free from combustible materials,
gasoline and other ammable
vapors and liquids.
1. Do not use this rebox as a wood-burning
replace. Use only decorative unvented room
heaters (log sets).
2. Do not add extra logs or ornaments such as pine
cones, vermiculite or rock wool. Using these
added items can cause sooting.
3. Use only the provided hood or appropriate
hood accessory. See Accessories on page 14.
4. Vent-free gas log heaters installed in these
reboxes require fresh air ventilation to run
properly. See Air for Combustion and Ventila-
tion, page 7.
5. Do not run rebox
• where ammable liquids or vapors are used
or stored
• under dusty conditions
6. Do not use this rebox to cook food or burn
paper or other objects.
7. Turn rebox off and let cool before servicing.
Only a qualied service person should service
and repair rebox.
8. Operating rebox above elevations of 4,500
feet could cause pilot outage.
9. Do not use the rebox if it has been under water
due to the shock hazard that could result with
the blower accessary (if installed) in place.

www.desatech.com 116208-01C4
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*. Firebox must be electrically
grounded in accordance with the National Electri-
cal 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
PRODUCT FEATURES
OPERATION
This rebox is designed for use with approved ANSI
Z21.11.2 decorative type unvented room heaters.
(Physical size limitations apply. Refer to minimum
rebox requirements supplied with log heater.) It
requires no outside venting or chimney making in-
stallation easy and inexpensive. When used without
the blower, the rebox requires no electricity mak-
ing it ideal for emergency backup heat.
REFRACTORY BRICk LINER
Your rebox may feature a concrete refractory
brick liner. As with all concrete liners, this liner
may develop slight cracks when exposed to heat.
These cracks will not affect the performance of
the replace or vent-free gas logs.
OUTSIDE AIR kIT ACCESSORY
The optional AK4 air kit provides additional out-
door air to improve burner efciency and reduce
build-up of condensation in the living space. Fol-
low the instructions included with the air kit.
LOCATING FIREBOX
PLANNING
Plan where you will install the rebox. This will
save time and money later when you install the re-
box. Before installation, consider the following:
1. Where the rebox will be located. Allow for
wall and ceiling clearances (see Installation
Clearances, page 10).
2. Everything needed to complete installation.
3. These models CANNOT be installed in a
bedroom unless the maximum Btu rating
of the installed vent-free log set is less than
10,000 Btu/hr.
4. Proper air for combustion and ventilation
(page 7).

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116208-01C 5
3 9/16"
3 7/16"
8 1/8"
8 1/8"
10 1/2"
9 3/4"
PRODUCT SPECIFICATIONS
29
1
/
2
"
23
15
/
16
"
3
9
/
16
"
17
3
/
8
"
25
1
/
8
"
29
1
/
2
"34
7
/
16
"
36
3
/
8
"
Standoffs
22
1
/
2
"
4"
32
1
/
4
"
36
1
/
2
"
14
15
/
16
"
6
5
/
16
"
3
3
/
8
"
8
15
/
16
"
9
3
/
4
"
12
1
/
4
"
19
1
/
2
"
16
11
/
16
"
1
9
/
16
"
3
9
/
16
"
8
1
/
8
"
2
13
/
16
"
8
5
/
8
"
4
1
/
4
"
3
1
/
2
"
Built-In
Side
Nailing
Flanges
Square
Gas Line
A
ccess
Holes
5/8"
Figure 1 - Firebox Dimensions (32" Models)
Right Side View
Firebox Top View
Front View
32" MODELS
Outside Air
Kit Location
(Optional)
Left Side
View with
Air Kit
Back View
Top View
29
1
/
2
"
23
15
/
16
"
3
9
/
16
"
17
3
/
8
"
25
1
/
8
"
29
1
/
2
"34
7
/
16
"
36
3
/
8
"
Standoffs
22
1
/
2
"
4"
32
1
/
4
"
36
1
/
2
"
14
15
/
16
"
6
5
/
16
"
3
3
/
8
"
8
15
/
16
"
9
3
/
4
"
12
1
/
4
"
19
1
/
2
"
16
11
/
16
"
1
9
/
16
"
3
9
/
16
"
8
1
/
8
"
2
13
/
16
"
8
5
/
8
"
4
1
/
4
"
3
1
/
2
"
Built-In
Side
Nailing
Flanges
Square
Gas Line
A
ccess
Holes
5/8"

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13
11
/
16
"
(36" Models)
15
9
/
16
"
(42" Models)
20
1
/
2
"
(36" Models)
24
1
/
8
"
(42" Models)
2
9
/
16
"
2
9
/
16
"
3
13
/
16
"
26" (36" Models)
29
1
/
2
" (42" Models)
35" (36" Models)
42" (42" Models)
Full Length Nailing Flanges, Top and Sides
8"
8"
8"
8"
2"
36" (36" Models) •
40" (42" Models)
40
1
/
4
" (36" Models) • 44
1
/
4
" (42" Models)
43"(36" Models) • 50"(42" Models)
35" (36" Models)
42" (42" Models)
36
1
/
8
" (36" Models)
36
1
/
8
" (42" Models)
24
15
/
16
" (36" Models)
26
7
/
8
" (42" Models)
9
9
/
16
"
(36" Models)
10
11
/
16
"
(42" Models)
21
1
/
8
" (36" Models)
23
1
/
16
" (42" Models)
41
1
/
8
"(36" Models) • 48
1
/
8
"(42" Models)
5/8"
4"
29
3
/
8
" (36" Models)
36
1
/
2
" (42" Models)
PRODUCT SPECIFICATIONS
Continued
Figure 2 - Firebox Dimensions (36" and 42" Models)
36" AND 42" MODELS
Note: If only one dimension is shown, the dimension is the same for both 36" and 42" models.
Firebox Top View
13
11
/
16
" (36" Models)
12
3
/
8
" (42" Models)
7
1
/
4
" (36" Models)
9" (42" Models)
2
9
/
16
"
10
1
/
2
"
(36" Models)
12
1
/
2
"
(42" Models)
Outside Air
Kit Location
(Optional)
Left Side
View with
Air Kit
13 11/16"
(36" Models)
15 9/16"
(42" Models)
201/2"
(36" Models)
241/8"
(42" Models)
2 9/16"
29/16"
313/16"
26" (36" Models)
29 1/2" (42" Models)
35" (36" Models)
42" (42" Models)
Full Length Nailing Flanges, Top and Sides
8"
8"
8"
8"
2"
36" (36" Models) •
40" (42" Models)
40
1
/
4
" (36" Models) • 44
1
/
4
" (42" Models)
43"(36" Models) • 50"(42" Models)
35" (36" Models)
42" (42" Models)
361/8" (36" Models)
361/8" (42" Models)
2415/16" (36" Models)
267/8" (42" Models)
99/16"
(36" Models)
1011/16"
(42" Models)
211/8" (36" Models)
231/16" (42" Models)
411/8"(36" Models) • 481/8"(42" Models)
5/8"
4"
293/8" (36" Models)
361/2" (42" Models)
Right
Side
View
Front View Back View
Top View

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116208-01C 7
AIR FOR COMBUSTION
AND VENTILATION
WARNING: This rebox shall
not be installed in a conned
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.
Today’s homes are built more energy efcient
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 ef-
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, reboxes, 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 classications:
1. Unusually Tight Construction
2. Unconned Space
3. Conned Space
The information on page 7 through 9 will help
you classify your space and provide adequate
ventilation.
Unusually Tight Construction
The air that leaks around doors and windows
may provide enough fresh air for combustion and
ventilation. However, in buildings of unusually
tight construction, you must provide additional
fresh air.
Unusually tight construction is dened 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 oors, 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 9.
If your home does not meet all of the
three criteria above, proceed to Determin-
ing Fresh-Air Flow for Firebox Location,
page 8.
Conned and Unconned Space
The National Fuel Gas Code, ANSI Z223.1/NFPA
54 denes a conned space as a space whose
volume is less than 50 cubic feet per 1,000 Btu
per hour (4.8 m3per kw) of the aggregate input
rating of all appliances installed in that space and
an unconned space as a space whose volume is
not less than 50 cubic feet per 1,000 Btu per hour
(4.8 m3per kw) of the aggregate input rating of
all appliances installed in that space. Rooms com-
municating directly with the space in which the
appliances are installed*, through openings not
furnished with doors, are considered a part of the
unconned space.
* Adjoining rooms are communicating only if
there are doorless passageways or ventilation grills
between them.

www.desatech.com 116208-01C8
DETERMINING FRESH-AIR FLOW
FOR HEATER LOCATION
Determining if You Have a Conned or
Unconned Space
Use this work sheet to determine if you have a
conned or unconned 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 22 ft. (length) x 18 ft.
(width) x 8 ft. (ceiling height) = 3168 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 = (Maximum
Btu/Hr the space can support)
Example: 3168 cu. ft. (volume of space) x
20 = 63,360 (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 replace logs __________ Btu/Hr
Other gas appliances* + ________ Btu/Hr
Total = ________ Btu/Hr
* Do not include direct-vent gas appliances.
Direct-vent draws combustion air from the
outdoors and vents to the outdoors.
Example:
Gas water heater __________ Btu/Hr
Vent-free heater + ________ Btu/Hr
Total = ________ Btu/Hr
AIR FOR COMBUSTION
AND VENTILATION
Continued
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: 63,360 Btu/Hr (maximum
the space can support)
79,000 Btu/Hr (actual amount
of Btu/Hr used)
The space in the above example is a conned
space because the actual Btu/Hr used is more than
the maximum Btu/Hr the space can support. You
must provide additional fresh air. Your options
are as follows:
A. Rework worksheet, adding the space of an
adjoining room. If the extra space provides an
unconfined space, remove door to adjoining
room or add ventilation grills between rooms. See
Ventilation Air From Inside Building, page 9.
B. Vent room directly to the outdoors. See Ven-
tilation Air From Outdoors, page 9.
C. Install a lower Btu/Hr heater, if lower Btu/Hr
size makes room unconned.
If the actual Btu/Hr used is less than the maxi-
mum Btu/Hr the space can support, the space is
an unconned 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 dened
as an unconned 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/NFPA54 Section 5.3
or applicable local codes.
40,000
39,000
79,000

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116208-01C 9
VENTILATION AIR
Ventilation Air From Inside Building
This fresh air would come from an adjoining un-
conned space. When ventilating to an adjoining
unconned space, you must provide two perma-
nent openings: one within 12" of the ceiling and
one within 12" of the oor 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 3). 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.
AIR FOR COMBUSTION
AND VENTILATION
Continued
Figure 4 - Ventilation Air from Outdoors
Figure 3 - Ventilation Air from Inside
Building
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 oor. 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.
INSTALLATION
WARNING: A qualied ser-
vice person must install rebox.
Follow all local codes.
WARNING: Never install the
rebox
• in a bedroom or bathroom*
• in a recreational vehicle
• where curtains, furniture,
clothing or other ammable
objects are less than 42" from
the front, top or sides of the
rebox
• in high trafc areas
• in windy or drafty areas
* Unless the installed log set is
rated at 10,000 Btu/Hr or less.
CAUTION: Log heaters
installed in this rebox create
warm air currents. These cur-
rents move heat to wall surfaces
next to rebox. Installing rebox
next to vinyl or cloth wall cover-
ings or operating rebox where
impurities (such as, but not
limited to, tobacco smoke, aro-
matic candles, cleaning uids,
oil or kerosene lamps, etc.) in
the air exist, may discolor walls
or cause odors.
Or
Remove
Door into
Adjoining
Room,
Option
3
Ventilation Grills
Into Adjoining Room,
Option 2
Ventilation
Grills
Into Adjoining
Room,
Option 1
12"
12"
Outlet
Air
Ventilated
Attic
Outlet
Air
Inlet
Air
Inlet Air Ventilated
Crawl Space
To
Crawl
Space
To Attic

www.desatech.com 116208-01C10
IMPORTANT: Vent-free gas log heaters add
moisture to the air. Although this is benecial,
installing firebox in rooms without enough
ventilation air may cause mildew to form from
too much moisture. See Air for Combustion and
Ventilation, page 7.
IMPORTANT: Make sure the rebox is level.
If firebox is not level, log set will not work
properly.
Note: Your rebox is designed to be used in zero
clearance installations. Wall or framing material
can be placed against any exterior surface on the
rear, sides, top or bottom of your rebox, except
where standoff spacers are integrally attached. If
standoff spacers are attached to your rebox, these
spacers can be placed directly against wall or fram-
ing materials. Use the dimensions shown for rough
opening to create the easiest installation.
Use 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
oor, ceiling and adjoining wall.
Carefully follow these instructions. This will
ensure safe installation.
Minimum Wall and Ceiling Clearances (see
Figure 5)
A. Clearances from the side of the fireplace
cabinet to any combustible material and wall
should follow diagram in Figure 5.
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
replace cabinet (see Figure 5).
B. Clearances from the top of the rebox opening
to the ceiling should not be less than 42".
C. When the rebox is installed on carpeting or
other combustible material, other than wood
ooring, the rebox should be installed on a
metal or wood panel extending the full width
and depth of the enclosure.
D. Clearances from the bottom of rebox to the
oor is 0".
INSTALLATION
Continued
Figure 5 - Minimum Clearance for
Combustible to Wall
*Minimum 16" from Side Wall
*
These reboxes can be installed as freestanding
units against a wall with the approved, optional
cabinet mantels (see Accessories, page 14) or as a
built-in unit. The clearances are the same for either
installation method.
CAUTION: Do not install
the rebox directly on carpet
or vinyl.
Example
Mantel Clearances for Built-In Installation
If placing custom mantel above built-in rebox,
you must meet the minimum allowable clear-
ance between mantel shelf and top of rebox
opening shown in Figure 6, page 11. These are
the minimum allowable mantel clearances for a
safe installation. Use larger clearances wherever
possible to minimize the heating of objects and
materials placed on the mantel.
CAUTION: Do not allow
the vent-free gas log heater
to touch or extend beyond the
replace screen.
NOTICE: Surface temperatures
of adjacent walls and mantels
become hot during operation.
Walls and mantels above the
firebox may become hot to
the touch. If installed properly,
these temperatures meet the
requirement of the national
product standard. Follow all
minimum clearances shown in
this manual.

www.desatech.com
116208-01C 11
NOTICE: If your installation does
notmeettheminimumclearances
shown, you must do one of the
following:
• raise the mantel to an accept-
able height
• remove the mantel
BUILT-IN FIREBOX INSTALLATION
Built-in installation of this rebox involves install-
ing rebox into a framed-in enclosure. This makes
the front of rebox ush with wall. Optional brass
trim accessories are available (see Accessories,
page 14). The brass trim will extend past sides
of rebox approximately 1/2". This will cover
the rough edges of the wall opening. If installing
a mantel above the rebox, you must follow the
clearances shown in Figure 6. Follow the instruc-
tions below to install the rebox in this manner.
INSTALLATION
Continued
1. Frame in rough opening. The rebox fram-
ing should be constructed of 2 x 4 lumber or
heavier. Use dimensions in Table 1 and rough
opening layout in Figure 7a.Adjust framing so
that rebox ushes with nished wall surface.
If installing in a corner, use dimensions in
Figures 7b, 7c and 7d for rough opening.
2. Install gas piping to rebox location. See
Installing Gas Line, page 12 and Connecting
to Gas Supply in log set owner’s manual.
3. Carefully set rebox in front of rough open-
ing with back of rebox inside wall opening.
IMPORTANT: If installing a perimeter trim
kit, see instructions included with trim acces-
sory. You must install shoulder screws from
trim kit now.
4. Carefully insert rebox into rough opening.
Figure 6 - Minimum Mantel Clearances
for Built-In Installation
Supplied
Firebox
Hood
Must Be
Used at
All Times
Wire-mesh
Screen
Firebox
Noncombustible
Material May
Project Off
this Surface
above the
Firebox Hood
Mantel Shelf
Note: Any portion of the
mantel shelf must NOT
extend beyond this profile.
12" 16" 20"
1
1
/ 2 "
6
3
/ 4 "
12"
Note: All vertical
measurements are from
top of fireplace hood
opening to bottom of
mantel shelf.
Wall board or facing
material (above
firebox) may be of
combustible material,
including decorative
mantel ornaments or
other similar projec-
tions off of the facing
material.
Framing
Material
These minimum clearances replace any other recommended
clearances supplied with your ANSI Z21.11.2 approved gas logs.
Rough Opening Dimensions for
Built-in Installation
Model
Front Width
(Inside to Inside) Height
Depth
(Min.)
32" 34 7/8" 36 3/4" 16 1/4"
36" 41 1/2" 40 1/2" 20 3/4"
42" 48 5/8" 44 1/2" 22 5/8"
Table 1
Figure 7 - Rough Opening for Installing
in Wall
Depth
(Minimum)
Width
(Inside to Inside)
Height
Figure 7a
37"
45°
41
1
/ 2 "
5
2
11
/
3
2
"
74"
TOP VIEW
FOR 36"
MODELS
Figure 7c
30"
45°
34
7
/ 8 "
42
7
/
16
"
60"
TOP VIEW
FOR 32"
MODELS
43"
45°
485/8"
6
0
13
/
16
"
86"
TOP VIEW
FOR 42"
MODELS
Figure 7d
Figure 7b

www.desatech.com 116208-01C12
5. Attach rebox to wall studs using nails or
wood screws through holes in nailing ange
(see Figure 8).
6. If using an optional perimeter trim kit, install
the trim after nal nishing and/or painting
of wall. See instructions included with trim
accessory for attaching trim.
7. Install and properly test gas log heater. Follow
installation instructions included with the vent-
free gas log heater that is being installed.
IMPORTANT: When finishing your firebox,
combustible materials such as wall board, gypsum
board, sheet rock, drywall, plywood, etc. may be
butted up next to the sides and top of the rebox.
Combustible materials should never overlap the
rebox front facing.
WARNING: Do not allow any
combustible materials to overlap
the rebox front facing.
IMPORTANT: Noncombustible materials such
as brick, tile, etc. may overlap the front facing,
but should never cover any necessary openings
like louvered slots.
WARNING: Do not allow
noncombustible materials to
cover any necessary openings
like louvered slots.
INSTALLATION
Continued
Figure 8 - Attaching Firebox to Wall
Studs
Nailing
Flanges
Nails or Wood
Screws
WARNING: Use only non-
combustible mortar or adhe-
sives when overlapping the front
facing with noncombustible
facing material.
INSTALLING FIREBOX USING
OPTIONAL ACCESSORY MANTELS
WARNING: A qualied ser-
vice person must install rebox.
Follow all local codes.
This rebox may be installed using a cabinet
mantel accessory against a wall in your home.
The rebox and cabinet mantel can be installed
directly on the oor. A trim kit is included with
the mantel accessories. Follow instructions with
mantel for installation.
INSTALLING GAS LINE
NOTICE: A qualied service per-
son must connect heater to gas
supply. Follow all local codes.
IMPORTANT: See Connecting to Gas Supply in
your log set owner’s manual for details on gas
hookup.
You may run the gas line from either side or back of
the rebox (see Figure 9, page 13). Decide which
side you want to run the gas line from.
Note: This is one option for installing shutoff
valve. Check local codes for equipment shutoff
valve location requirements.
Locate the recessed knockout in one of the re-
brick liners (see Figures 9 and 10, page 13). Firmly
tap the center of the knockout with a chisel until it
is released. Carefully chisel the rough edges of the
hole you have made to smooth edges. This hole
will line up with the hole in the outer casing.
CAUTION: Do not use exces-
sive force to remove the knock-
out. Too much force may damage
the rebrick concrete insert.

www.desatech.com
116208-01C 13
INSTALLATION
Continued
Figure 9 - Installing Gas Line and
Equipment Shutoff Valve (Model May
Vary From Illustration)
Knockout
Locations
(Knock Out
One Hole) Gas Line
Hole
Equipment
Shutoff
Valves (Install
One)
Figure 10 - Location of Knockout for
Gas Line
Knockout Chisel
Firebrick Side Wall
Remove
this Area
Side
View
Figure 11 - Air Kit Handle Location
Air Kit
Handle
Screen
Pocket
COMBUSTION AIR kIT MODEL Ak4
(OPTIONAL)
The outside air kit may be installed on the left side of
the replace only. The vent can be installed through
any outside wall a minimum of three feet below
replace termination cap. The handle to operate the
damper door for the outside air inlet will be located
inside the left “screen pocket” of the rebox (see Fig-
ure 11). Pull the handle to open or push to close.
CAUTION: Air inlet ducts are
not to terminate in attic space.
INSTALLING FIREPLACE HOOD
AND SCREEN
1. Attach hood and front panel assembly by
snapping the panel assembly into replace
opening. (see Figure 12).
2. Insert each screen rod through all rings located
at top of screen.
3. Insert rst rod into rear hole in left side of
rebox. Fasten rod to rear hole near center
of rebox using #10 x 3/8" Phillips screw
provided (see Figure 13, page 14).
4. Insert other rod into front hole on right side
of rebox and fasten using remaining Phil-
lips screw.
Figure 12 - Hood Placement
(Model May Vary From Illustration)
Hood

www.desatech.com 116208-01C14
REPLACEMENT PARTS
Note: Use only original replacement parts. This
will protect your warranty coverage for parts
replaced under warranty.
PARTS UNDER WARRANTY
Contact authorized dealers of this product. If
they can’t supply original replacement part(s),
call DESA’s Technical Service Department at
1-866-672-6040.
When calling DESA, have ready
• your name
• your address
• model and serial numbers of your rebox
• how rebox was malfunctioning
• type of gas used (propane/LP or natural gas)
• purchase date
Usually, we will ask you to return the part to the
factory.
PARTS NOT UNDER WARRANTY
Contact authorized dealers of this product. If they
can’t supply original replacement part(s), call DESA
at 1-866-672-6040 for referral information.
When calling DESA, have ready
• model number of your rebox
• the replacement part number
Note: The rebox identication label (including
model number, serial number, clearances, etc.) is
located on the right front edge of the rebox.
INSTALLATION
Continued
TECHNICAL SERVICE
You may have further questions about installation,
operation or troubleshooting. If so, contact DESA’s
Technical Service Department at 1-866-672-6040.
When calling, please have your model and serial
numbers of your rebox ready.
You can also visit DESA’s technical services web
site at www.desatech.com.
ACCESSORIES
NOTICE: All accessories may not be
available for all replace models.
Purchase these rebox accessories from your local
dealer. If they can not supply these accessories,
call DESA’s Sales Department at 1-866-672-6040
for information. You can also write to the address
listed on the back page of this manual.
EQUIPMENT SHUTOFF VALVE
GA5010
All Models. Equipment shutoff valve with 1/8"
NPT tap.
CLEANING kIT - GCk/CCk
All Models. Your vent-free gas appliance requires
regular cleaning and maintenance to prevent
performance problems. This kit gives you the
tools and instructions to make it easy to clean
all critical areas of your appliance.
FIRE CRACkEL - CF6-A
Creates the sound of a real burning re.
HOODS
H36B - 36" Brushed Brass
H36P - 36" Platinum
H36PB - 36" Polished Brass
H42B - 42" Brushed Brass
H42P - 42" Platinum
H42PB - 42" Polished Brass
CORNER CABINET MANTEL WITH
BASE AND PERIMETER TRIM (Not
Shown)
C32AU - 32" Unnished, Traditional Design
C32AOS - Light Oak Finish, Traditional
Design
C32HS - 32" Dark Oak Finish, Classic
Design
C36AU - 36" Unnished, Traditional Design
GMC56F - 36" Light Oak Finish, Classic
Design
Ideal for space saving installations.
Figure 13 - Installing Fireplace Screen
(Model May Vary From Illustration)
Screw
Rear Hole
Top View of Rod Layout
Rod
Front Hole
Ring
Screen
Identication
Label
Location

www.desatech.com
116208-01C 15
ACCESSORIES
Continued
WALL CABINET MANTEL AND BASE
ACCESSORY WITH FIREPLACE
PERIMETER TRIM (Not Shown)
W32AU - 32" Unnished, Traditional Design
W32AOS - 32" Light Oak Finish, Traditional
Design
CMA311W - 32" Painted White, Traditional
Design with Dentil Molding
CMA306FA - 32" Light Oak Finish,
Traditional Design with Dentil Molding
CMA312FB - 32" Dark Oak Finish, Classic
Design
W32KCSA - 32" Cherry Finish, Neo-
Classical Design
W32KPA - 32" Painted White, Neo-
Classical Design
CMA305UA - 32" Unnished, Georgian
Design with Columns
GMC90FA - 32" Light Oak Finish, Georgian
Design with Columns
W32DS - 32" Dark Oak Finish, Keystone
Design
W32GOSA - 32" Dark Oak Finish, Mission
Design
W32IP - 32" Painted White, Ultra/Click-n-
Brick Surround
W36AU - 36" Unnished, Traditional Design
GMC55F - 36" Light Oak Finish, Traditional
Design
W36DS - 36" Dark Oak Finish, Keystone
Design
W36IP - 36" Painted White, Ultra/Click 'n
Brick Surround
Note: 42" mantels not available at this time.
PERIMETER TRIM
PT32 - 32" Black
PT32B - 32" Brushed Brass
PT32PB - 32" Polished Brass
PT32P - 32" Platinum
PT36 - 36" Black
PT36B - 36" Brushed Brass
PT36PB - 36" Polished Brass
PT36P - 36" Platinum
PT42 - 42" Black
PT42B - 42" Brushed Brass
PT42PB - 42" Polished Brass
PT42P - 42" Platinum
OUTSIDE AIR kIT
Ak4 - Complete Kit w/ Collar, Hood and 3'
of Flex Tube
Ak4X - Collar and Hood (accepts any
length of 4" ex tube)
Ak4B - 50pc. Bulk Collar Only Kits
Optional kits provide additional air to reduce
build-up of condensation that occurs in today’s
tightly constructed homes.

www.desatech.com 116208-01C16
1
2
3
5
6
4
8
9
10
11
12
13
7
14
15 16 23 25
23
22
20
19
17
18
21
23
24
23
24
ILLUSTRATED PARTS BREAKDOWN
MODELS
VFF-32S-AKA AND VTFB32

www.desatech.com
116208-01C 17
kEY
NO. PART NO. DESCRIPTION QTY.
1 116207-02 Screen • • 2
2 108700-01 Screen Rod • • 2
3 11418 Push-On Nut • • 2
4 116631-01 Hood Assembly Panel • • 1
5 ** Face Weldment • • 1
6 108434-03 Left Refractory • 1
108434-04 Left Refractory • 1
7 108430-03 Rear Refractory • 1
108430-04 Rear Refractory • 1
8 108432-03 Right Refractory • 1
108432-04 Right Refractory • 1
9 116201-02 Bottom Refractory • 1
116201-04 Bottom Refractory • 1
10 ** Firebox Bottom • • 1
11 ** Firebox Surround • • 1
12 116531-01 Refractory Retainer • • 2
13 116532-01 Rear Refractory Retainer • • 1
14 108413-01 Firebox Top Shield • • 1
15 ** Firebox Top • • 1
16 108415-01 Starter Pipe Collar • • 1
17 ** Insulation Pan • • 1
18 ** Fireplace Top Insulation • • 1
19 ** Fireplace Top • • 1
20 20280 Top Spacer • • 4
21 ** Fireplace Surround • • 1
22 108654-01 Gas Conduit Left and Right Assembly • • 2
23 21171 Gas Knock-Out Cover • • 5
24 107128-01 Gas Conduit • • 2
25 20042 Cover Plate • • 1
** Not a eld replaceable part.
PARTS LIST
This list contains replaceable parts used in your rebox. When ordering parts, follow the instructions
listed under Replacement Parts on page 14 of this manual.
VFF-32S-AKA VTFB32

www.desatech.com 116208-01C18
ILLUSTRATED PARTS BREAKDOWN
MODELS
VFF-36S-AKA, VFF-42S-AKA, VTFB36 AND VTFB42
1
2
3
5
22
4
24
25
6
9
7
23
8
10
11 12
23
18
20
21
16
15
13
14
17
18
19
18
20
21

www.desatech.com
116208-01C 19
PARTS LIST
This list contains replaceable parts used in your rebox. When ordering parts, follow the instructions
listed under Replacement Parts on page 14 of this manual.
kEY
NO. PART NO. DESCRIPTION QTY.
1 116207-01 Screen • • 2
116207-03 Screen • • 2
2 107839-01 Screen Rod • • • • 2
3 11418 Push-On Nut • • • • 2
4 112857-05 Hood Assembly Panel • • 1
112857-09 Hood Assembly Panel • • 1
5 ** Face Weldment • • • • 1
6 ** Firebox Bottom • • • • 1
7 116531-01 Refractory Retainer, Sides •••• 2
8 116532-01 Refractory Retainer, Rear •••• 1
9 ** Firebox Surround • • • • 1
10 ** Firebox Top Shield • • • • 1
11 ** Firebox Top • • • • 1
12 106687-01 Damper Can Collar (Spacer) • • • • 1
13 ** Insulation Pan • • • • 1
14 ** Fireplace Top Insulation • • • • 1
15 ** Fireplace Top • • • • 1
16 20280 Top Spacer • • • • 4
17 ** Fireplace Surround • • • • 1
18 21171 Gas Knock-Out Cover • • • • 3
19 107128-01 Gas Conduit • • • • 2
20 21379 Gas Conduit • • • • 2
21 271380-01 Gas Conduit • • • • 2
22 106658-04 Left Refractory • 1
107812-04 Left Refractory • 1
106658-05 Left Refractory • 1
107812-05 Left Refractory • 1
23 106660-04 Rear Refractory • 1
107816-04 Rear Refractory • 1
106660-05 Rear Refractory • 1
107816-05 Rear Refractory • 1
24 106659-04 Right Refractory • 1
107814-04 Right Refractory • 1
106659-05 Right Refractory • 1
107814-05 Right Refractory • 1
25 116201-01 Bottom Refractory • 1
116201-03 Bottom Refractory •1
116201-05 Bottom Refractory •1
116201-06 Bottom Refractory •1
** Not a eld replaceable part.
VFF-36S-AkA VFF-42S-AKA VTFB36 VTFB42

LIMITED WARRANTY
VENT-FREE FIREBOX
DESA warrants this product to be free from defects in materials and components for four (4) years from the date
of rst purchase, provided that the product has been properly installed, operated and maintained in accordance
with all applicable instructions. To make a claim under this warranty the Bill of Sale or cancelled check must
be presented.
This warranty is extended only to the original retail purchaser. This warranty covers the cost of part(s) required to
restore this heater to proper operating condition and an allowance for labor when provided by a DESA Authorized
Service Center. Warranty part(s) MUST be obtained through authorized dealers of this product and/or DESA who
will provide original factory replacement parts. Failure to use original factory replacement parts voids this warranty.
The heater MUST be installed by a qualied installer in accordance with all local codes and instructions furnished
with the unit.
This warranty does not apply to parts that are not in original condition because of normal wear and tear or parts
that fail or become damaged as a result of misuse, accidents, lack of proper maintenance or defects caused by
improper installation. As with all concrete liners, this liner may develop slight cracks when exposed to heat. This
cracking is considered normal. Travel, diagnostic cost, labor, transportation and any and all such other costs related
to repairing a defective heater will be the responsibility of the owner.
TO THE FULL EXTENT ALLOWED BY THE LAW OF THE JURISDICTION THAT GOVERNS THE SALE OF
THE PRODUCT; THIS EXPRESS WARRANTY EXCLUDES ANY AND ALL OTHER EXPRESSED WARRAN-
TIES AND LIMITS THE DURATION OF ANY AND ALL IMPLIED WARRANTIES, INCLUDING WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE TO FOUR (4) YEARS ON ALL
COMPONENTS FROM THE DATE OF FIRST PURCHASE; AND DESA’S LIABILITY IS HEREBY LIMITED
TO THE PURCHASE PRICE OF THE PRODUCT AND DESA SHALL NOT BE LIABLE FOR ANY OTHER
DAMAGES WHATSOEVER INCLUDING INDIRECT, INCIDENTAL OR CONSEQUENTIAL DAMAGES.
Some states do not allow a limitation on how long an implied warranty lasts or an exclusion or limitation of
incidental or consequential damages, so the above limitation on implied warranties or exclusion or limitation on
damages may not apply to you.
This warranty gives you specic legal rights and you may also have other rights that vary from state to state.
For information about this warranty write:
2701 South Harbor Blvd.
Santa Ana, CA 92704
116208-01
Rev. C
02/06NOT A UPC
WARRANTY INFORMATION
KEEP THIS WARRANTY
Model
Serial No.
Date Purchased
Always specify model and serial numbers when communicating with the factory.
We reserve the right to amend these specications at any time without notice. The only warranty applicable is our
standard written warranty. We make no other warranty, expressed or implied.
116208 01