Comfortflame CUVF36C Quick start guide

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WARNING: If the information in this manual is not
followed 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 AN APPLIANCE IN THIS FIREBOX
UNLESS THIS FIREBOX MEETS THE MINIMUM DIMEN-
SIONS REQUIRED FOR THE INSTALLATION.
This rebox has been tested and approved 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
CIRCULATING MODELS:
CUVF36C AND CUVF42C
PFS
®
US

www.fmiproducts.com 126330-01A2
SAFETY
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.
WARNING: Improper
installation, adjustment,
alteration, service or
maintenance can cause
injury or property dam-
age. Refer to this manual
for correct installation
and operational proce-
dures. For assistance or
additional information
consult a qualified in-
staller, service agency or
the gas supplier.
This appliance may be in-
stalled in an aftermarket,*
permanently located,
manufactured (mobile)
home, where not prohib-
ited by local codes.
* Aftermarket: Completion of sale, not for
purpose of resale, from the manufacturer
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.
Do not place clothing or other
ammable material on or near
the appliance. Never place any
objects in the rebox or on
logs.
TABLE OF CONTENTS
Safety .................................................................. 2
Local Codes......................................................... 3
Product Features................................................. 4
Locating Firebox.................................................. 4
Product Specications......................................... 5
Air For Combustion and Ventilation ..................... 7
Installation ........................................................... 9
Replacement Parts............................................ 19
Technical Service............................................... 19
Parts .................................................................. 20
Accessories ....................................................... 22
Warranty ..............................................Back Cover

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126330-01A 3
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.
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.
SAFETY
Continued
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 appropri-
ate hood accessory. See Accessories on
page 22.
4. Vent-free gas log heaters installed in these
reboxes require fresh air ventilation to
run properly. See Air for Combustion and
Ventilation, 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 servic-
ing. 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 un-
der water due to the shock hazard that
could result with the blower accessary (if
installed) in place.
LOCAL CODES
Install and use heater with care. Follow all
local codes. In the absence of local codes,
use the latest edition of The National Fuel Gas
Code, ANSI Z223.1/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
State of Massachusetts: The installation
must be made by a licensed plumber or
gas tter in the Commonwealth of Mas-
sachusetts.
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
Commonwealth of Massachusetts.

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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 vent-
ing or chimney making installation easy and
inexpensive. When used without the blower,
the rebox requires no electricity making it
ideal for emergency backup heat.
BLOWER ACCESSORY
The circulating models will accept either a ro-
tary type fan (model BK) or the triple radial fan
blower system (model BK3) accessories. The
blower circulates heated air from the rebox
into the room. Use of blower is optional.
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 perfor-
mance of the replace or vent-free gas logs.
OUTSIDE AIR KIT ACCESSORY
The optional AK4 / AK4F air kit provides addi-
tional outdoor air to improve burner efciency
and reduce build-up of condensation in living
space. Follow instructions included with air kit.
LOCATING FIREBOX
PLANNING
Plan where you will install the rebox. This will
save time and money later when you install
the rebox. Before installation, consider the
following:
1. Where the rebox will be located. Allow for
wall and ceiling clearances (see Installa-
tion 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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126330-01A 5
PRODUCT SPECIFICATIONS
Continued
Figure 1 - Product Specifications 36'' Models
41.127
43.039
34.890
36.074
7.049
20.962
8.063
7.410
8.513
11.492
3.277
2.550
8.175
8.525
8.331
8.175
13.892
10.349
24.934
21.081
6.043 29.101
26.366
40.250
Right Side ViewLeft Side View Front View
Firebox Top View
36" MODELS
Outside
Air Kit
Location
Electrical
Outlet

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PRODUCT SPECIFICATIONS
Continued
Figure 3 - Product Specifications 42'' Models
40.037 40.035
48.136 41.896
42.000
7.083
23.964 22.281
3.120
44.253
7.564
10.532
13.369
2.520
8.153
3.265
10.768
10.436
2.523
8.153
14.233
12.582
1.360
50.045
23.216
4.479
6.028 36.143
27.117
4.359
2.315
Right Side ViewLeft Side View Front View
Firebox Top View
42" MODELS
Outside
Air Kit
Location
Electrical
Outlet

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126330-01A 7
AIR FOR COMBUSTION AND 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 un-
usually 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 Determining
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 m3 per kw) of the ag-
gregate 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 m3 per kw)
of the aggregate input rating of all appliances
installed in that space. Rooms communicating
directly with the space in which the appliances
are installed*, through openings not furnished
with doors, are considered a part of the un-
conned space.
* Adjoining rooms are communicating only if
there are doorless passageways or ventilation
grills between them.
WARNING: This heater shall
not be installed in a room or
space unless the required vol-
ume of indoor combustion air
is provided by the method de-
scribed in the National Fuel Gas
Code, ANSI Z223.1/NFPA 54, the
International Fuel Gas Code, or
applicable local codes. 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 ap-
pliances 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 appli-
ances.
PROVIDING ADEQUATE
VENTILATION
The following are excerpts from National Fuel
Gas Code, ANSI Z223.1/NFPA 54, Air for
Combustion and Ventilation.
All spaces in homes fall into one of the three
following ventilation classications:
1. Unusually Tight Construction
2. Unconned Space
3. Conned Space
The information on page 6 through 8 will help
you classify your space and provide adequate
ventilation.

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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 deter-
mine the maximum Btu/Hr the space can
support.
_____ (volume of space) x 20 = (Maxi-
mum 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 appli-
ances 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 appli-
ances. 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 sup-
port. 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 unconned 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
Ventilation 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
maximum 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 operated does
not meet the required volume for
indoor combustion air, combus-
tion and ventilation air shall be
provided by one of the methods
described in the National Fuel
Gas Code, ANSI Z223.1/NFPA
54, the International Fuel Gas
Code, or applicable local codes.
40,000
39,000
79,000

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126330-01A 9
VENTILATION AIR
Ventilation Air From Inside Building
This fresh air would come from an adjoining
unconned space. When ventilating to an
adjoining unconned space, you must provide
two permanent 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 3). You can also remove door
into adjoining room (see option 3, Figure 3).
Follow the National Fuel Gas Code, ANSI
Z223.1/NFPA 54, Air for Combustion and
Ventilation for required size of ventilation
grills or ducts.
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 perma-
nent 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, 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 thermo-
stat-controlled power vent. Heated air entering
the attic will activate the power vent.
INSTALLATION
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
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, cloth-
ing 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
in a bedroom or 6,000 Btu/Hr
or less in a bathroom.
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.
AIR FOR COMBUSTION AND VENTILATION
Continued

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IMPORTANT: Vent-free gas log heaters add
moisture to the air. Although this is benecial,
installing rebox 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 firebox is level.
If rebox 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 framing ma-
terials. 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 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 com-
bustible material must be 4" from the side
of the replace cabinet (see Figure 5).
B. Clearances from the top of rebox opening
to ceiling should not be less than 42".
C. When rebox is installed on carpeting or
other combustible material, other than
wood ooring, rebox should be installed
on a metal or wood panel extending the
full width and depth of enclosure.
D. Clearances from bottom of rebox to the
oor is 0".
These reboxes can be installed as freestand-
ing units against a wall with the approved,
INSTALLATION
Continued
*Minimum 16" from Side Wall
*
optional cabinet mantels (see Accessories,
page 22) or as a built-in unit. 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.
Figure 5 - Minimum Clearance for
Combustible to Wall

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126330-01A 11
0" CLEARANCE
*14 1/2"
50 3/8"
71 1/4"
35 5/8"
41 3/8"
0" CLEARANCE
48 1/4"
82"
58"
*17"
41"
*17"
FOR 36" MODELS
FOR 42" MODELS
INSTALLATION
Figure 6 - Minimum Mantel Clearances
for Built-In Installation
Figure 7 - Rough Opening Dimensions
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.
These minimum
clearances replace any
other recommended
clearances supplied
with your ANSI Z21.11.2
approved gas logs.
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
Rough Opening Dimensions for
Built-in Installation
Model
Front Width
(Inside to Inside) Height
Depth
(Min.)
36" 41 3/8"40 1/4"21 1/8"
42" 48 1/4"43 3/4"23 1/2"
Table 1
NOTICE: If your installation does
not meet the minimum clear-
ances 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
installing rebox into a framed-in enclosure.
This makes the front of rebox ush with wall.
Optional brass trim accessories are available
(see Accessories, page 22). 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 instructions below to
install the rebox in this manner.
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 firebox flushes
with nished wall surface. If installing in
a corner, use dimensions in Figures 7b,
7c and for rough opening.
2. Install gas piping to rebox location. See In-
stalling Gas Line,page 13 and Connecting
to Gas Supply in log set owner’s manual.
* These dimensions allow for min. Clearances
to a 45° projected side wall. However, clear-
ances to projected mantel trims and facings
are allowed within a min. Of 16" to a perpen-
dicular wall as shown in gure 5, on page 10.
Depth
(Minimum)
Width
(Inside to Inside)
Height
Figure
7a
Figure
7b
Figure
7c

www.fmiproducts.com 126330-01A12
IMPORTANT: If installing blower accessory,
see page 13.
3. Carefully set rebox in front of rough open-
ing with back of rebox inside wall open-
ing. IMPORTANT: If installing a perimeter
trim kit, see instructions included with
trim accessory. You must install shoulder
screws from trim kit now.
4. Carefully insert rebox into rough opening.
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 nishing your rebox,
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.
INSTALLATION
Continued
Figure 8 - Attaching Firebox to Wall Studs
(Model May Vary From Illustration)
Nailing
Flanges
Nails or Wood
Screws
IMPORTANT: Noncombustible materials such
as brick, tile, etc. may overlap the front facing,
but should never cover any necessary open-
ings like louvered slots.
WARNING: Do not allow
noncombustible materials to
cover any necessary openings
like louvered slots.
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.
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)

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126330-01A 13
INSTALLATION
Continued
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 of
the rebox (see Figure 9, page 12). 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 shut-
off valve location requirements.
Locate the recessed knockout in one of the
rebrick sidewall liners (see Figure 9 on page
12 and Figure 10). 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.
Figure 10 - Location of Knockout for
Gas Line
Knockout Chisel
Firebrick Side Wall
Remove
this Area
Side
View
INSTALLING OPTIONAL BLOWER
ACCESSORIES
NOTICE: The rebox identica-
tion label (including model num-
ber, serial number, clearances,
etc.) is located in the right side
screen pocket area on the front
of the rebox. See Figures 22
and 23, page 18.
NOTICE: If a log set is installed
in the rebox, disconnect log
set from gas supply and remove
from rebox. Contact a qualied
service person to do this.
Note: Appearance of rebox may vary de-
pending on model.
There are two (2) blower accessory options for
use in this replace. Blower accessory models
are BK and BK3. Model BK is a rotary squirrel
cage type blower with magnetic attachment
and variable speed control. The BK3 is a triple
fan blower system with an on/off rocker switch.
Wiring Instructions
1. Remove electrical cover plate with
bushing from replace by removing 2
sheet metal screws as shown in Figure
11, page 14.
2. Slide power source wiring through
electrical bushing opening and electri-
cal cover plate and make all necessary
connections.
3. Slide all wiring connections in electrical
housing as shown in Figure 11, page 14.
4. Secure electrical cover plate with screws
previously removed.
Note: Electrical housing and cover plate have
sharp edges. Wear protective gloves.

www.fmiproducts.com 126330-01A14
Figure 12 - Accessing Blower Compartment
(Controls Not Shown for Clarity)
Front Refractory Panel
Lower
Louver Panel
Control
Access
Cover
ON/OFF
Rocker
Switch
INSTALLATION
Continued
Decide which way you intend to gain access
into the bottom rear of the rebox to install the
blower accessory. The lower front panel can
be removed easily by snapping out the front
with a at blade screwdriver. Use caution not
to scratch any surfaces. Models with louvered
front panels can also be removed by inserting
ngertips between slots and gently pulling out.
DO NOT FORCE. The panels are actually
held in place by means of a retention dimple
embossed on the edge of removable panels.
Accessibility to the bottom can also be gained
through the access panel underneath the bot-
tom front refractory brick liner. Lift the bottom
front refractory brick liner up and out of the
rebox oor, exposing the rectangular shaped
access panel (see Figure 12). The sides and
back refractory brick liner pieces do not have
to be removed. Lift access panel out by using
nger holes. Blower accessory BK or BK3 can
now be installed.
Electrical
Bushing
Electrical
Cover
Plate
Rocker
Switch
Figure 11 - Fan Switch-Electrical Bushing
Electrical
Housing
Wire Nut (3x)
(Not Supplied)
Outer Wrapper
of Fireplace
Electrical Cover
Plate and
Electrical Bushing
Fireplace Chassis
Ground
To Power
Source
Receptacle
(Supplied)
Power Source Wiring
(Not Supplied)
Prewired Receptacle
and Ground
Sheet
Metal
Screws
Duplex Electrical Outlet
Figure 13 - Accessing Duplex Electrical
Outlet Installed in Bottom Right Side of
Firebox
WARNING: If there is a duplex
electrical outlet installed in the
right side of the bottom of the
replace base area (see Figure
13), be sure that the electrical
power to the outlet is turned off
before proceeding with blower
installation. Failure to do this
may result in serious injury.

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126330-01A 15
INSTALLATION
Continued
5. Remove ON/OFF switch from louver
panel by pressing top and bottom retain-
ing clips (see Figure 12, page 14).
6. Place louver panel, louvers pointing up,
back into framed opening. Align control shaft
with rectangular opening by sliding control
bracket along ange (see Figure 15).
7. Fully seat louver panel into frame open-
ing by gently pressing along ends until all
dimpled retainers have snapped in place.
8. Place control knob, provided, onto control
shaft (see Figure 15).
9. Check to make sure power cord is com-
pletely clear of blower wheel and there are
no foreign objects in blower wheel. Also,
double check all wire leads and make
sure wire routing is not pinched or in a
precarious position. Correct accordingly.
CAUTION: Never touch
blower wheel while in operation.
10. Turn on power to duplex outlet if previ-
ously turned off per warning in column 2,
page 14.
11. Plug in blower power cord to duplex outlet
(see Figure 13, page 14).
12. Turn blower on and check for operation.
Turn blower off by turning knob fully coun-
terclockwise before continuing.
Figure 15 - Attaching Speed Control to
Firebox with Panel Louvers
Control
Shaft
Control
Knob
Lock Nut
Speed
Control
Bracket
Lower
Louver
Firebox Face
Hearth
Pan
Flange
Screw
Head and
Top Hole
on Bracket
Lower
Flange
Figure 14 - Blower Model BK
Magnetic Strips
Exhaust
Port
Screw
Green
Ground
Wire
Spade
Terminals
Side View
Firebox Bottom
Air Flow
Direction
Blower
Installed
After
Lower
Panel
Removed
Blower
Location Magnets
Model BK Installation
1. Be certain that all wire terminals are
securely attached to terminals on blower
motor and that the screw retaining the
green ground wire is tight (see Figure 14).
2. Place blower against lower rear wall of
rebox outer wrapper with exhaust port di-
rected upward. Depending on your model,
you may have to carefully route the blower
assembly past controls and brackets and
position blower inside back opening. The
blower will be held in position against the
back wall by magnets incorporated onto
blower housing (see Figure 14).
3. Position speed control bracket over ange
on hearth pan by sliding it up between
rebox face and hearth pan ange, then
down until seated onto lower ange of
louver opening (see Figure 15).
4. Remove metal locknut from plastic control
shaft by turning locknut with pliers coun-
terclockwise. Mount speed control box
by placing plastic control shaft through
bottom hole on speed control bracket. Top
screw head on control box will t inside top
hole on bracket (see Figure 15). Secure
speed control to bracket with previously
removed lock nut by pushing and turning
lock nut with pliers clockwise until it is tight
against bracket.

www.fmiproducts.com 126330-01A16
INSTALLATION
Continued
Figure 16 - Location of Wiring Diagram
Decal (Model May Vary From Illustration)
Wiring Diagram
Decal 12" in
Front of Blower
Variable
Fan Switch
Green
White
On
110/115
V.A.C.
Blower
Motor
Black
Off 1
2 Black
13. Peel off backing paper and stick supplied
wiring diagram decal on rebox bottom
approximately 12" in from of blower (see
Figure 16).
14. Replace all panels and/or brick bottom
panel if previously removed.
Model BK3 Installation
1. Place BK3 fan assembly between two leg
stands with fan blades pointing toward
rear of replace (see Figure 17).
2. Using screws provided, fasten upper
ange of blower bracket to hearth pan and
end anges to leg stands (see Figure 17).
Note: The wire assembly must be ar-
ranged in front of and away from fan
blades to reach power receptacle plug.
Figure 17 - Mounting BK3 Blower
BK3 Blower
Screws
for Leg
Stands
Screws at Upper Flange
3. Connect wire connectors to rear of switch
terminals on rocker switch located in lower
louver panel (see Figure 18).
4. Check to make sure power cord is com-
pletely clear of blower and that there are
no foreign objects in blower. Also, double
check all wire leads and make sure wire
routing is not pinched or in a precarious
position. Correct accordingly.
5. Turn on power to duplex outlet if previously
turned off per warning in column 1, page 13.
6. Plug in blower power cord to duplex outlet
(see Figure 14).
7. Using ON/OFF rocker switch to turn
blower on and check for operation. Turn
blower off before continuing.
8. Peel off backing paper and stick supplied
wiring diagram decal on rebox bottom
approximately 12" in from of blower (see
Figure 16).
9. Replace all panels and/or brick bottom
panel if previously removed.

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126330-01A 17
INSTALLATION
Continued
Figure 18 - Connecting Rocker Switch
ON/OFF
Rocker
Switch
Wire Harness
Connectors
Switch
Terminals
Black
110/115
V.A.C.
Blower
Motor
No. 1
Black
Hot
Nuetral
ON/OFF
Panel Switch
Blower
Motor
No. 2
Blower
Motor
No. 3
Figure 19 - BK3 Wiring Diagram
OPTIONAL OUTSIDE AIR KIT
(MODEL AK4/AK4F)
Installation of outside air kit should be per-
formed during rough framing of replace due
to the nature of it's location. Outside combus-
tion air is accessed through a vented crawl
space (AK4F) or through a sidewall (AK4).
See Figure 20.
CAUTION: Combustion air
inlet ducts shall not terminate
in attic space.
The maximum height for the
air vent can not exceed 3 feet
below the ue gas outlet of the
termination.
Figure 20 - Outside Air Kit
Secure to Collars with Metal Tape, Screws
or Straps (Min. of 1/4" x 20" in size)
Air Inlet
Location
Must Allow
For Bushes
or Snow
Vent Hood
Required for
Wall Installation
Air Inlet
Eyebrow
Vented Crawl Space
(Check Local Codes
Before Installing in a
Vented Crawl Space)

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INSTALLATION
Continued
Figure 23 - Screen Pocket Location
INSTALLING FIREPLACE HOOD
AND SCREEN
1. Attach hood to rebox using screws pro-
vided (see Figure 21).
2. Insert each 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 22).
4. Insert other rod into front hole on right
side of rebox and fasten using remaining
Phillips screw.
LOCATING ACCESS COVER PLATE
Sheet metal cover plates located underneath
front hearth refractory may have shifted or moved
out of place while replace was in transit. These
cover plates must be kept in the proper location
prior to using the replace (See Figure 24).
Figure 21 - Screw and Hood Placement
(Model May Vary From Illustration)
Figure 22 - 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
Screen Pocket
Location
Screws
Hood
Figure 24 - Locating Access Cover Plate
Access
Panel

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126330-01A 19
REPLACEMENT PARTS
Note: Use only original replacement parts.
This will protect your warranty coverage for
parts replaced under warranty.
Contact authorized dealers of this product. If
they can’t supply original replacement part(s),
call FMI PRODUCTS, LLC at 1-866-328-4537.
When calling, have ready:
• your name
• your address
• model and serial numbers of your heater
• how heater was malfunctioning
• purchase date
Usually, we will ask you to return the part to
the factory.
TECHNICAL SERVICE
You may have further questions about installa-
tion, operation, or troubleshooting. If so, contact
FMI PRODUCTS, LLC at 1-866-328-4537.
When calling please have your model and serial
numbers of your heater ready.
You can also visit our web site at
www.fmiproducts.com.

www.fmiproducts.com 126330-01A20
1
2
3
4
8
12
13
14 15
21
23/24
20
19
18
16
26
27
11
28
5
25
29
10
9
6
22
17
PARTS
MODELS
CUVF36C AND CUVF42C