Desa VJM36 Series Quick start guide

Save this manual for future reference.
For more information, visit www.desatech.com
SAVE THIS BOOK
This book is valuable. In addition to instructing you
on how to install and maintain your appliance, it also
contains information that will enable you to obtain re-
placement parts or accessory items when needed. Keep
it with your other important papers.
This fireplace is approved for use as a wood burning
fireplace or for use with a vented gas log approved to
ANS Z21.60, Z21.84 or RGA 2-72 standards or for use
with a vent-free gas log heater approved to ANS Z21.11.2
standard.
This wood burning fireplace complies with UL127-
CAN/ULS-S610-M87 standard as a FACTORY BUILT
APPLIANCE.
FOR CANADA: The authority having jurisdiction (such
as the municipal building department, fire department,
etc.) should be contacted before installation to deter-
mine the need to obtain a permit.
RESIDENTIAL AND OUTDOOR WOODBURNING FIREPLACE
OWNER’S OPERATION AND INSTALLATION MANUAL
(V)JM36, (V)JM42 AND (V)JM50
WOOD BURNING MASONRY FIREPLACES WITH INSULATION

www.desatech.com 117541-01A
2
WARNING: Improper installation, adjustment, altera-
tion, service or maintenance can cause injury, property
damage or loss of life. Refer to this manual for assis-
tance or additional information. Consult a qualified
installer or local distributor.
TABLE OF CONTENTS
Safety Information ............................................... 2
Specifications ...................................................... 5
Fireplace Installation ........................................... 6
Venting Installation .............................................. 8
Optional Gas Line Installation ........................... 12
Brick Installation ................................................ 13
Glass Door Installation ...................................... 20
Operation and Maintenance Guidelines ............ 21
Technical Service .............................................. 22
Replacement and Accessory Parts ................... 23
SAFETY INFORMATION
IMPORTANT: Check local codes
before installing this fireplace.
Before beginning the installation of the fireplace,
read these instructions through completely.
• This DESA fireplace and its components are
safe when installed according to this installation
manual. Unless you use DESA components,
which have been designed and tested for the
fireplace system, you may cause a fire hazard.
• The DESA warranty will be voided by and
DESA disclaims any responsibility for the
following actions.
a. Modification of the fireplace, components,
doors, air inlet system and damper control.
b. Use of any component part not manufac-
tured or approved by DESA in combination
with a DESA fireplace system.
Proper installation is the most important step in
ensuring safe and continuous operation of the
fireplace. Consult the local building codes as to
the particular requirements concerned with the
installation of all factory built fireplaces.
WARNING: Do not install a
fireplace insert in this box unless
the manufacturer's instructions
with the insert specifically state
this fireplace has been tested for
use with this insert.
FOR YOUR SAFETY
• Do not store or use gasoline
or any other flammable vapors
or liquids in the vicinity of this
or any other appliance.
• Due to high temperatures, the
appliance should be located
out of traffic and away from
furniture and draperies.
• Do not place clothing or other
flammable materials on or near
the appliance.
• Never leave children unat-
tended when a fire is burning
in the fireplace.
WARNING: Use solid wood
or processed solid fuel firelogs
only. When processed wood fuel
fire logs are used, do not poke or
stir the logs while they are burn-
ing. Use only fire logs that have
been evaluated for the application
in fireplace and refer to fire log
warnings and caution markings
on packaging prior to use.
This fireplace is not intended to be
used as a substitute for a furnace
to heat an entire home. Use for
supplemental heat only.

www.desatech.com
117541-01A 3
SPECIFICATIONS Continued
MODELS VJM36 AND JM36
10.50
15.375
0.625 45.000
29.00
26.625
22.000
36.000
21.500
3.50
10.75
1.000
49.000
8.000
58.000
30.000
36.000
45.000
12.000
9.50
7.0
67.000
7.500
11/2" AIR SPACE
BACK AND SIDES
0" TO
BOTTOM
GAS LINE
KNOCKOUTS
12" EACH SIDE
COMBUSTIBLE
WALL BOARD
NO COMBUSTIBLE
MATERIAL ON FACE
MINIMUM 12" TO
PERPENDICULAR
SIDEWALL
HEARTH EXTENSION
60" X 20"
1" CHIMNEY AIRSPACE
CLEARANCE TO
COMBUSTIBLE MATERIAL
TERMINATION
SQUARE CHASE-TOP
ROUND TOP TERMINATION
OUTSIDE AIR
20.000
GAS LINE
KNOCK OUTS
AIR KIT
KNOCK OUT
LEFT SIDE

www.desatech.com 117541-01A
4
SPECIFICATIONS Continued
MODELS VJM42 AND JM42
10.50
17.00
0.625 51.000
30.500
28.500
21.250
41.250
23.500
24.250
3.50
13.00
1.000
49.000
8.000
58.000
30.000
42.000
51.000
12.000
9.50
8.50
67.000
11.000
GAS LINE
KNOCK OUTS
AIR KIT
KNOCK OUT
LEFT SIDE
OUTSIDE AIR
11/2" AIR SPACE
BACK AND SIDES
0" TO
BOTTOM
GAS LINE
KNOCKOUTS
12" EACH SIDE
COMBUSTIBLE
WALL BOARD
NO COMBUSTIBLE
MATERIAL ON FACE
MINIMUM 18" TO
PERPENDICULAR
SIDEWALL
HEARTH EXTENSION
66" X 20"
2" CHIMNEY AIRSPACE
CLEARANCE TO
COMBUSTIBLE MATERIAL
ROUND TOP TERMINATION
TERMINATION
SQUARE CHASE-TOP

www.desatech.com
117541-01A 5
SPECIFICATIONS
MODELS VJM50 AND JM50
10.50
17.00
50.000
23.500
32.750
3.50
13.00
9.50
8.50
2" CHIMNEY AIRSPACE
CLEARANCE TO
COMBUSTIBLE MATERIAL
TERMINATION
SQUARE CHASE-TOP
ROUND TOP TERMINATION
COMBUSTIBLE
WALL BOARD
NO COMBUSTIBLE
MATERIAL ON FACE
0" TO
BOTTOM
OUTSIDE AIR
11/2" AIR SPACE
BACK AND SIDES
GAS LINE
KNOCKOUTS
12" EACH SIDE
MINIMUM 18" TO
PERPENDICULAR
SIDEWALL
HEARTH EXTENSION
74" X 20"
0.625 59.000
38.500
28.500
21.250
11.000
1.000
49.000
8.000
58.000
30.000
50.000
59.000
12.000
67.000
LEFT SIDE
GAS LINE
KNOCK OUTS
AIR KIT
KNOCK OUT

www.desatech.com 117541-01A
6
FIREPLACE INSTALLATION
SELECTING LOCATION
To determine the safest and most efficient location
for the fireplace, you must take into consideration
the following guidelines:
1. The location must allow for proper clearances
(see Figures 1 and 2).
2. Consider a location where the fireplace will
not be affected by drafts, air conditioning
ducts, windows or doors.
3. A location that avoids the cutting of joists or
roof rafters will make installation easier.
4. An outside air kit is available with this fireplace
(see Optional Outside Air Kit on page 8).
MINIMUM CLEARANCE TO
COMBUSTIBLES
Back and sides of fireplace 1 1/2" minimum*
Front of fireplace 48" minimum
Floor** 0" minimum
Perpendicular wall to opening 18" minimum
12" min. JM36
Top spacers 0" minimum
Mantel clearances see Mantels, page 7
Chimney outer pipe surface 2" minimum
1" min. JM36
* Not required at nailing flanges
** See step 2 of Framing
WARNING: Do not pack re-
quired air spaces with insulation
or other materials.
Minimum/Maximum Chimney Height for
Residential Installation
The minimum height of the chimney, measured
from the base of the fireplace to the flue gas outlet
of the termination, is 16 feet for straight flue or a
flue with one elbow set. The maximum distance
between elbows is 6 feet. For systems with two
elbow sets, the minimum height is 22 feet. The
maximum height of any system is 50 feet. This
measurement includes the fireplace, chimney sec-
tions and the height of the termination assembly
at the level of the flue gas outlet (see Figure 15,
page 11).
Minimum/Maximum Chimney Height for
Outdoor Installation
The minimum height of the chimney, measured
from the base of the fireplace to the flue gas outlet
of the termination, is 9.5 feet (minimum of 4 feet
of chimney pipe sections required for outdoor
installation).
FRAMING
1. Frame the opening for the fireplace using the
dimensions shown in Figures 1 and 2.
2. If the fireplace is to be installed directly on
carpeting, tile (other than ceramic) or any
combustible material other than wood floor-
ing, the fireplace must be installed upon a
metal or wood panel extending the full width
and depth of the fireplace.
3. Set the fireplace directly in front of this open-
ing and slide the unit back until the nailing
flanges touch the side framing.
4. Check the level of the fireplace and shim with
sheet metal if necessary.
5. Before securing fireplace to prepared framing,
the ember protector (provided) must be placed
between the hearth extension (not supplied)
and under the bottom front edge of the fire-
place to protect against glowing embers falling
through. If the fireplace is to be installed on
a raised platform, a Z-type ember protector
(not supplied) must be fabricated to fit your
required platform height. The ember protector
should extend under the fireplace a minimum
of 1 1/2". The ember protector should be made
of galvanized sheet metal (28 gauge minimum
to prevent corrosion.
6. Using screws or nails, secure the fireplace to
the framing through flanges located on the
sides of the fireplace.
30.125
59.250 (50")
58.125
67.125
51.250 (42")
45.250 (36") 28.250 (36")
Figure 1 - Framing Dimensions
71.000 (50")
100.000 (50")
65.000 (42")
92.000 (42")
86.500 (36")
61.000 (36")
MAINTAIN 1 1/2"
CLEARANCE AT
SIDES AND BACK
OF FIREPLACE
1 1/2" CLEARANCE
NOT REQUIRED AT
NAILING FLANGES
Figure 2 - Corner Installation

www.desatech.com
117541-01A 7
Note: For outdoor installations, the fireplace en-
closure must allow for adequate drainage and fresh
air ventilation. It is recommended that a sealed,
corrosion resistant catch pan with provision for
drainage be installed under the fireplace within
the fireplace enclosure.
HEARTH EXTENSION
A hearth extension projecting a minimum of 20"
in front of and a minimum of 12" beyond each
side of the fireplace opening is required to protect
combustible floor construction in front of the fire-
place. Fabricate a hearth extension using a material
which meets the following specifications: a layer
of noncombustible, inorganic material having a
thermal conductivity of K=0.84 BTU IN/FT, HR.
F (or less) at 1" thick. For example, if the material
selected has a K factor of 0.25, such as glass fiber,
the following formula would apply:
0.25 x 1.0" = 0.30" thickness required
0.84
Thermal conductivity "K" of materials can be
obtained from the manufacturer or supplier of the
noncombustible material. If the hearth extension
is to be covered, use noncombustible material such
as tile, slate, brick, concrete, metal, glass, marble,
stone, etc. Provide a means to prevent the hearth
extension from shifting and seal gap between the
fireplace frame and hearth extension with a non-
combustible material (see Figure 3).
WARNING: Hearth extension
is to be installed only as shown
in Figure 3.
FIREPLACE INSTALLATION
Continued
Figure 3 - Hearth Extension
Seal Gap
Fireplace Front
Ember Protector
Fireplace Front
Raised Hearth
Fireplace Front
Elevated
Ember Protector
Ember Protector
Seal Gap
Hearth
Extension
MANTELS
A mantel may be installed if desired (see Figure
4). Woodwork such as wood trims, mantels or any
other combustible material projecting from the
front face must not be placed within 12" (JM36) or
18" (JM42/50) of the fireplace opening. Combus-
tible materials above 12" (JM36) or 18" (JM42/50)
and projecting more than 1 1/2" from the fireplace
must not be placed less than 15" (JM36) or 21"
(JM42/50) from the top opening of the fireplace
(NFPA STD 211, Sec. 7-3.3.3).
Mantels or any other combustible material also
may come up to the side edge of the black metal
face of the fireplace just as long as the projection
from the front face fall within the limit shown in
Figure 4.
12 1/4" Ref.
6"
Ref.
15" Min.
(JM36)
21" Min.
(JM42/50)
12" Min. (JM36)
18" Min. (JM42/50)
11/2" Max.
3" Nom.
33°
Combustible
Material
Safe
Zone for
Projection of
Combustible
Materials
Fireplace
Opening
Upper
Section of
Fireplace
Figure 4 - Mantel Clearances to
Combustible Material
FIREBOX
SAFE ZONE
Top View of Fireplace
3" Max.
4.5"
Min. to
Perpendicular
Side Wall
12" - JM36
18" - JM42/50
7.75" (JM36)
11.5" (JM42/50)
33°

www.desatech.com 117541-01A
8
Figure 6 - Lineal Gain
LINEAL GAIN
PART NO. DESCRIPTION GAIN (IN)
Georgian Fireplace 66 1/2 "
12-12DM
12-12HT Pipe Section 10 5/8
"
18-12DM
18-12HT Pipe Section 16 5/8
"
24-12DM
24-12HT Pipe Section 23 5/8
"
36-12DM
36-12HT Pipe Section 34 5/8
"
48-12DM
48-12HT Pipe Section 46 5/8
"
RLT-12D
RLT-12HT Round Termination 7 3/4
"
*
STL-12D Square Chase-Top
with Slip Section
7 " to 15 " *
* The lineal gain for the terminations is mea-
sured to the flue gas outlet height.
Hemmed
End
12 3/8"
Stainless
Inner Pipe
12" Galvanized
Outer Pipe
ASSEMBLY AND INSTALLATION OF
DOUBLE WALL CHIMNEY SYSTEM
Each double wall chimney section consists of a
galvanized outer pipe, a stainless steel inner flue
pipe and a wire spacer. The pipe sections must be as-
sembled independently as the chimney is installed.
When connecting chimney directly to the fireplace,
the inner flue pipe section must be installed first with
the lanced side up. The outer pipe section can then
be installed over 5 the flue pipe section with the
hemmed end up. Press down on each pipe section
until the lances securely engage the hem on the fire-
place starter. The wire will assure the proper spacing
between the inner and outer pipe sections.
Continue to assemble chimney sections as outlined
above, making sure that both the inner and outer
pipe sections are locked together. When install-
ing double wall snap-lock chimney together, it is
important to assure the joint between the chimney
sections is locked. Check by pulling chimney
upward after locking. The chimney will not come
apart if properly locked. It is not necessary to add
screws to keep the chimney together (exception
- see Figure 9, page 10).
VENTING INSTALLATION
OPTIONAL OUTSIDE AIR KIT
(MODEL AK4/AK4F)
The installation of an outside air kit should be per-
formed during the rough framing of the fireplace
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).
CAUTION: Combustion air
inlet ducts shall not terminate
in attic space.
Figure 5 - 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)
CHIMNEY PIPE
The DESA chimney system consists of 12, 18, 24,
36 and 48" snap-lock, double-wall pipe segments,
planned for maximum adaptability to individual
site requirements. Actual lengths gained after
fitting overlaps must be taken into consideration
(lineal gain) and are given in the lineal gain chart
(see Figure 6). Lineal Gain is the actual mea-
surable length of a part after two or more parts
are connected. For Canada, use chimney parts
designated "HT".
WARNING: The opening in the
collar around the chimney at the
top of the fireplace must not be
obstructed. Never use blown insula-
tion to fill the chimney enclosure.

www.desatech.com
117541-01A 9
VENTING INSTALLATION
Continued
USING ELBOW OFFSETS (30E-12DM)
1. To achieve desired offset, you may install combi-
nations of 12, 18, 24, 36 and 48" length of double
wall pipe (see offset chart and Figure 7).
OFFSET RISE CHIMNEY LENGTH
A B 48" 36" 24" 18" 12"
4 3/8" 16 3/8" ELBOW SET ONLY
9 3/4" 25 1/2" 1
12 3/4" 30 3/4" 1
15" 34 3/4" 1
18" 40" 1 1
21 1/4" 46 1/4" 1
23 3/4" 49 1/4" 1 1
27 3/4" 56 3/4" 1
30" 60 3/4" 1 1
33" 66" 1 1
36" 71" 1 1
38 1/4" 75" 2
41 1/4" 80 1/4" 1 1 1
45" 86 3/4" 2
46 3/4" 89 1/2" 1 1 1
51" 97" 1 1
53 1/4" 101" 2 1
56 1/4" 106 1/4" 2
59 1/4" 111 1/2" 1 1 1
61 3/4" 115 1/2" 2 1
64 3/4" 120 3/4" 2 1
68 1/4" 127" 1 2
70" 130" 2 1 1
74 1/4" 137 1/2" 1 2 1
76 3/4" 141 1/2" 1 2 1
79 3/4" 146 3/4" 4
OFFSET CHART (22-50 FT. SYSTEM HEIGHT)
Figure 7 - Typical Offset Terminations
Return
Elbow
Offset
Elbow
Return
Elbow
Offset
Elbow
6' Max.
6' Max.
6' Max.
6' Max.
6' Max.
6' Max.
Return
Elbow
Offset
Elbow
Offset
Elbow
Return
Elbow
A B C
Offset
Elbow
Ceiling
Support Pipe
12S-12DM
Return
Elbow
Figure 8 - Ceiling Support Pipe
12S-12DM
2" Min.
Straps
Straps
Straps
Straps
Detail A
Return Elbow
Detail B
Angle Firestop
See Detail A
See Detail B
2.
Chimney weight above offset rests on return
elbow. Straps must be securely nailed to rafters
or joists (see Figure 8, details a & b).
3. Maximum length of pipe between supports
(return elbow or 12S-12DM) is 6' of angle
run. Maximum of two 6' angle run sections
per chimney system (see Figure 7).
4. All pipe connections between the offset and
return must be secured with two screws on
the outer pipe only (see Figure 9, page 10).
Do not penetrate the inner stainless.

www.desatech.com 117541-01A
10
VENTING INSTALLATION
Continued
Figure 9 - Elbow Offset
B
A
Screws
FIRESTOP SPACERS (FS-10,
1100EFS-10DM FOR JM36)
Firestop spacers are required at each point where
the chimney penetrates a floor space. Their purpose
is to establish and maintain the required clearance
between the chimney and the combustible materials.
When the pipe passes through a framed opening into
a living space above, the firestop must be placed onto
the ceiling from below as shown in Figure 10.
They also provide complete separation from one floor
space to another or attic space as required by most
codes. When the double wall pipe passes through a
framed opening into an attic space, the firestop must
be placed into an attic floor as shown in Figure 11.
Figure 10 - Firestop Spacer with Living
Space Above Ceiling
Figure 11 - Firestop Spacer with Attic
Space Above Ceiling
Existing
Ceiling
Frame
Firestop
Spacer
Screws or
Staples
(Min. of 8)
Firestop
Spacer
Screws or Staples
(Min. of 8)
PENETRATING THE ROOF
To maintain a 1" (JM36) or 2" (JM42/JM50) clear-
ance to the pipe on a roof with a pitch, a rectangular
opening must be cut.
1. Determine the center point through which the
pipe will penetrate the roof.
2. Determine the center point of the roof. Pitch
is the distance the roof drops over a given
span, usually 12". A 6/12 pitch means that
the roof drops 6" for each 12" one measure
horizontally down from the roof rafters.
3. Use the roof opening chart (Figure 12) to
determine the correct opening length and
flashing required.
17" Min.
(432mm) 30" Min.
(762mm)
1" Min.
(25mm)
1" Min.
(25mm)
1" Min.
(25mm)
Opening "A"
Roof Opening JM36
Pitch Slope Opening "A"
Max.
Used Flashing
Model No.
Flat 0° 17" V6F-10DM
0-
6/12 26.6° 19" V6F-10DM
6/12-
12/12 45.0° 24" V12F-10DM
Roof Opening JM42/50
Pitch Slope Opening "A"
Max.
Used Flashing
Model No.
Flat 0° 19.5" V6F-10DM
0-
6/12 26.6° 22' V6F-10DM
6/12-
12/12 45.0° 27" V12F-10DM
Existing
Ceiling
Frame
19.5" Min.
(495mm)
30" Min.
(762mm)
2" Min.
(51mm)
2" Min.
(51mm)
2" Min.
(51mm)
Opening "A"
Figure 12 - Roof Opening Measurements

www.desatech.com
117541-01A 11
VENTING INSTALLATION
Continued
4. Remove the shingles around the opening
measured. Cut out this section.
5. Add the next sections of the pipe until the
end penetrates the roof line. Check to see that
the proper clearances are maintained. Extend
chimney by adding sections of double wall
pipe until pipe is minimum of 30" above the
highest point of the roof cutout. Termination
and chimney must extend a minimum of
36" above the highest point where it passes
through the roof.
FLASHING INSTALLATION (V6F-10DM
OR V12F-10DM)
Determine the flashing to be used with the roof
opening chart. Slide flashing over pipe until base
is flat against roof. Replace as many shingles as
needed to cover exposed area and flashing base.
Secure in position by nailing through shingles
(see Figure 13). DO NOT NAIL THROUGH
FLASHING CONE.
Installing Flashing on a Metal Roof
When installing the flashing on a metal roof, it is
required that putty tape be used between the flash-
ing and the roof. The flashing must be secured to
the roof using #8 x 3/4" screws and then sealed
with roof coating to prevent leakage through the
screw holes. A roof coating must also be applied
around the perimeter of the flashing to provide a
proper seal.
Nail Only
Outer
Perimeter
of Flashing
Storm
Collar
Flashing
Cone
Underlap
Shingles
at Bottom
Overlap
Shingles Top
and Sides Only
Figure 13 - Flashing Installation
Storm Collar Installation (SC2-1)
Place storm collar over pipe and slide down until
it is snug against the open edge of the flashing (see
Figure 14). Apply waterproof caulk around the
perimeter of the collar to provide a proper seal.
Figure 14 - Storm Collar
Chimney
Pipe
Waterproof
Caulk
Storm
Collar Flashing
Terminations/Spark Arrestor
The fireplace system must be terminated with the
listed round top or chase terminations. In any case,
refer to the installation instructions supplied with
the termination.
CAUTION: Do not seal open-
ings on the rooftop flashing. Fol-
low the installation instructions
provided with the termination
being used.
Secure
Termination
to Outer
Pipe with 3
Screws
RTL-10D
Level of
Flue Gas
Outlet
Stainless
Inner Flue
Pipe
Waterproof
Caulking
Storm
Collar
Flashing
Underlap
Shingles
Figure 15 - Termination

www.desatech.com 117541-01A
12
CHASE INSTALLATIONS
Instructions for chase installations are included
with the chase style termination chosen. In a
multiple chase installation, be sure to provide
adequate distance between terminations to prevent
smoke spillage from one termination to another.
We suggest that terminations be separated at least
24", center to center and stacked at a vertical height
difference of 18" (see Figure 16).
Note: If a decorative shroud is to be installed,
contact the manufacturer for specifications.
VENTING INSTALLATION
Continued
10 FOOT RULE
All flue gas outlet chimney terminations must
extend a minimum of 3 feet in height above the
highest point where it passes through the roof and
must be at least 2 feet above the highest point of
the roof that is within a horizontal distance of 10
feet (see Figure 17).
FINISHING THE FIREPLACE
Combustible materials, such as wallboard, gypsum
board, sheet rock, drywall, plywood, etc. may make
direct contact with sides and top around the fireplace
face. It is important that combustible materials do
not overlap the face itself. Brick, glass, tile or other
noncombustible materials may overlap the front
face provided they do not obstruct essential open-
ings like louvered slots or any other opening. When
overlapping with a noncombustible facing material,
use only noncombustible mortar or adhesive.
OPTIONAL GAS LINE
INSTALLATION
Gas line hook up should be done by your supplier
or a qualified service person.
Note: Before you proceed, make sure your gas
supply is turned off.
Use only a 1/2" black iron pipe and appropriate
fittings.
1. Remove knockout indentation on refractory or
firebrick wall located above the refractory hearth
floor. The knockout indentation must be firmly
tapped with any solid object such as a 1/2" dowel
until it is released. Remove fragmented portions
of refractory (see Figure 18, page 13).
2. Remove gas line cover plate located on either
side of fireplace and pull out insulation from gas
line conduit sleeve. Save insulation for reuse.
Replace screws.
3. Run a 1/2" black iron gas line into the fireplace
through the rear at gas line conduit sleeve (if
using a raised platform, add height). Provide
sufficient gas line into fireplace chamber for
fitting connection (see Figure 19, page 13).
Note: Secure incoming gas line to wood
framing to provide rigidity for threaded end.
4. Repack insulation around gas line and into
sleeve opening. Seal any gaps between gas line
and refractory knockout hole with refractory ce-
ment or commercial furnace cement, Install the
gas appliance or cap-off gas line if desired.
24" Min.
24" Min.
18"
Min.
Typ.
Figure 16 - Multiple Chase Installation
10'
2' Min.
10'
3' Min.
2' Min. 3' Min.
Level of
Flue Gas
Outlet
Figure 17 - 10 Foot Rule

www.desatech.com
117541-01A 13
OPTIONAL GAS LINE
INSTALLATION
Continued
CAUTION: All gas piping
and connections must be tested
for leaks after the installation
is completed. After ensuring
that the gas valve is on, apply
soap and water solution to all
connections and joints. Bubbles
forming show a leak. Correct
all leaks at once. DO NOT USE
AN OPEN FLAME FOR LEAK
TESTING AND DO NOT OPER-
ATE ANY APPLIANCE IF A LEAK
IS DETECTED. LEAK TESTING
SHOULD BE DONE BY A QUALI-
FIED SERVICE PERSON.
WARNING: Do not oper-
ate an unvented gas log set in
this fireplace with the chimney
removed.
If you install a decorative gas appliance (vented
gas log), the decorative gas appliance must comply
with the Standard for Decorative Gas Appliance
for Installation in Solid Fuel Burning Fireplaces,
ANS Z21.60, Z21.84 or RG 2-72 and shall also be
installed in accordance with the National Fuel Gas
Code, ANSI 7223NFPA 54 latest edition.
WARNING: If the fireplace
has been used for wood burning,
the firebox and chimney must be
cleaned of soot, creosote and
ashes be a qualified chimney
cleaner. Creosote will ignite if
heavily heated.
WARNING: When using a
decorative vented gas log, the
damper must be removed or
permanently locked in the fully
open position and the glass
doors must be in the fully open
position.
Figure 18 - Gas Line Knockout
Side
Firebrick
Finished
Side
Refractory
Knockout
Plug
Outside of
Fireplace
Gas Line
Conduit
Insulation
Gas
Conduit
Cover
1/2" Dowel
Seal
Opening
with
Refractory
Cement
Outside of
Fireplace
Gas
Line
Conduit
Repack
Insulation
Incoming
1/2" Black
Iron Pipe
Side
Firebrick
Finished
Side
Provide Enough Threaded
End for Fitting Connection
Figure 19 - Gas Line Installation
BRICK INSTALLATION
Installation of brick should be
done after the fireplace is placed
in a permanent location.
The brick housing panels are already installed in
the firebox. Each housing is stamped with a letter
(full size bricks are not stamped). These letters will
help identify the brick when installing. It is impor-
tant to install these bricks exactly as instructed.
Press the brick firmly into the brick housing until
it maps. The groove line on the side of the brick
will come in contact with the flange on the brick
housing. This secures the brick into the housing.
See Figure 20 on page 14.
The bricks are packaged in four separate boxes.
These boxes are labeled by sections of the fire-
box.
Box #1 - Hearth Panel
Box #2 - Rear Panel
Box #3 - Left or Right Panel
Box #3 - Left or Right Panel

www.desatech.com 117541-01A
14
Install the bricks one at a time starting with the
hearth panel followed by the rear panel and then
the left or right panel. It is important to install the
bricks in sequence. Note: The left and right panels
have identical bricks. Please note, full size bricks
are NOT stamped.
Use brick “AO” (JM42 and JM50 only) or “AR”
(JM36 only) if an optional gas line is installed.
Mount brick “AO” or “AR” as shown in Figure
20. It is important that the knockout hole is in
its proper locations. The knockout hole on brick
“AO” or “AR” should align with the hole on the
brick housing.
BRICK INSTALLATION
Continued
Figure 20 - Installing Brick
Brick Stamped
Letter
Location
Brick Housing
Flanges
LEFT PANEL REAR PANELRIGHT PANEL
HEARTH PANEL
AH QP
AG
AC
AE AFFULL
AF
AF
AP
AC AG
AT AG
Q
AI QAI
CC
DD
FULL
C
D
C
G
FULL FULL
G
FULLFULL
FULL FULL
FULL
HH
II
MM
AB
L
FULL
D
C
AS
C
FULL FULL
FULL
FULL FULL
FULL
AL AL
FULL
FULL
FULL
FULL
AE
AE
FULL
FULL
Q
AC
AE
AN
FULL
AC
AE
AE
FULL
FULL
AH
AG
AG
AF
AG
AF
AF
P
AB L L
AS
OR
**AR**AR
AP
OR
BRICK INSTALLATION FOR MODEL (V)JM36
**See instruction above before
installing brick "AR"
INSTALLING BRICK "AO" OR "AR"
Use brick “AO” (JM42 and JM50 only) or “AR”
(JM36 only) if an optional gas line is installed.
Mount brick “AO” or “AR” as shown in Figure
21. It is important that the knockout hole is in
its proper location. The knockout hole on brick
“AO” or “AR” should align with the hole on the
brick housing.
LEFT PANEL
D1510
FULLFULL
D
C
B
AN
RIGHT PANEL
B
C
AN
FULL
AO
FULL D
OR
AR
AR
AO
OR
LEFT PANEL
D1510
FULLFULL
D
C
B
AN
RIGHT PANEL
B
C
AN
FULL
AO
FULL D
OR
AR
AR
AO
OR
Figure 21 - Installing Brick “AO” or “AR”

www.desatech.com
117541-01A 15
LEFT PANEL REAR PANELRIGHT PANEL
HEARTH PANEL
D1509B
RQO
D
C
A
BFULL
FULL
AP
**AO
B
AC
B
AT C
Z Q Z
F
E
F
E
F
AM
AM
FFULL
AL
FULL
FULL
E
FFULL FULL
FULL
E
FFULL FULL
UU
Y
V V
WW
KKKKX
LLLLAA
FULL
FULL
FULL FULL
FULL
FULL FULL
D
D
OR
B
B
B
CFULL
C
C
FULL
FULL
FULL
AN
FULL
FULL
A
D
D
FULL
O
FULL
A
R
Q
D
FULL
FULL FULL FULL
FULL FULL
FULL FULL FULL
X
AA
Y
AP
**AO
OR
BRICK INSTALLATION FOR MODEL (V)JM42
BRICK INSTALLATION
Continued
**See instruction on page 14
before installing brick "AO"
REAR PANEL RIGHT PANEL
HEARTH PANEL
R
FULL
FULL
FULLFULL
FULL
FULLFULL
B
D
C A
B
C A
C
B
AN
Q
FULL
P Q Q
EE
F F
FULL
FULLFULL FULL
EFULL FULL E
FFULL FULL FULL F
EFULL FULL E
AL AL AL AQ
G
FULL FULL FULL
G
FULLFULL
FULL FULL FULL
FULL FULL
HH
I I
M M
J
N
J
NL
K K
L
K
L
K
L
FULL FULL
QO
D
D
FULL
AP
OR
**AO
FULL
FULL
Q
C
C
FULLD
C
FULLD
FULL D
O
A
AT
FULL
B
A
FULL
FULL
B
B
RP
LEFT PANEL
AQ
**AO
AP
OR
BRICK INSTALLATION FOR MODEL (V)JM50
**See instruction on
page 14 before install-
ing brick "AO"

www.desatech.com 117541-01A
16
BRICK INSTALLATION
Continued
BRICK MATRIX FOR MODEL (V)JM36
BRICK MATRIX Full A B C D E F G H I J K L M N O P
Box #1 Hearth-36 8 - - - - - - 2 2 2 - - 3 2 - - -
Box #2 Rear-36 7 - - 6 4 - - - - - - - - - - - -
Box #3 Left or Right-36 5 - - - - - - - - - - - - - - - 1
Box #3 Left or Right-36 5 - - - - - - - - - - - - - - - 1
TOTAL 25 0 0 6 4 0 0 2 2 2 0 0 3 2 0 0 2
BRICK MATRIX FOR MODEL (V)JM36 (Continued)
BRICK MATRIX Q R S T U V W X Y Z AA AB AC AD
Box #1 Hearth-36 - - - - - - - - - - - 2 - -
Box #2 Rear-36 2 - - - - - - - - - - - - -
Box #3 Left or Right-36 1 - - - - - - - - - - - 2 -
Box #3 Left or Right-36 1 - - - - - - - - - - - 2 -
TOTAL 4 0 0 0 0 0 0 0 0 0 0 2 4 0
BRICK MATRIX FOR MODEL (V)JM36 (Continued)
BRICK MATRIX AE AF AG AH AI AJ AK AL AM AN AO AP AQ
Box #1 Hearth-36 - - - - - - - - - - - - -
Box #2 Rear-36 - - - - 2 - - 2 - - - - -
Box #3 Left or Right-36 3 3 3 1 - - - - - 1 - 1 -
Box #3 Left or Right-36 3 3 3 1 - - - - - - - 1 -
TOTAL 6662200201020
BRICK MATRIX - (V)JM36
BRICK MATRIX FOR MODEL (V)JM36 (Continued)
BRICK MATRIX AR AS AT TOTAL
Box #1 Hearth-36 - - - 21
Box #2 Rear-36 - 2 - 25
Box #3 Left or Right-36 1 - - 22
Box #3 Left or Right-36 1 - 1 22
TOTAL 2 2 1 90

www.desatech.com
117541-01A 17
BRICK INSTALLATION
Continued
BRICK MATRIX FOR MODEL (V)JM42
BRICK MATRIX Full A B C D E F G H I J K L M N O P
Box #1 Hearth-42 10 - - - - - - - - - - 4 4 - - - -
Box #2 Rear-42 8 - - - - 4 6 - - - - - - - - - -
Box #3 Left or Right-42 8 2 3 3 3 - - - - - - - - - - 1 -
Box #3 Left or Right-42 8 2 3 3 3 - - - - - - - - - - 1 -
TOTAL 34 4 6 6 6 4 6 0 0 0 0 4 4 0 0 2 0
BRICK MATRIX FOR MODEL (V)JM42 (Continued)
BRICK MATRIX Q R S T U V W X Y Z AA AB AC AD
Box #1 Hearth-42 - - - - 2 2 2 2 2 - 2 - - -
Box #2 Rear-42 1 - - - - - - - - - - - - -
Box #3 Left or Right-42 1 1 - - - - - - - - - - - -
Box #3 Left or Right-42 1 1 - - - - - - - - - - - -
TOTAL 3 2 0 0 2 2 2 2 2 0 2 0 0 0
BRICK MATRIX - (V)JM42
BRICK MATRIX FOR MODEL (V)JM42 (Continued)
BRICK MATRIX AR AS AT TOTAL
Box #1 Hearth-42 - - - 30
Box #2 Rear-42 - - - 24
Box #3 Left or Right-42 - - - 25
Box #3 Left or Right-42 - - 1 25
TOTAL 0 0 1 104
BRICK MATRIX FOR MODEL (V)JM42 (Continued)
BRICK MATRIX AE AF AG AH AI AJ AK AL AM AN AO AP AQ
Box #1 Hearth-42 - - - - - - - - - - - - -
Box #2 Rear-42 - - - - - - - 1 2 - - - -
Box #3 Left or Right-42 - - - - - - - - - 1 1 1 -
Box #3 Left or Right-42 - - - - - - - - - - 1 1 -
TOTAL 0000000121220

www.desatech.com 117541-01A
18
BRICK INSTALLATION
Continued
BRICK MATRIX FOR MODEL (V)JM50
BRICK MATRIX Full A B C D E F G H I J K L M N O P
Box #1 Hearth-50 12 - - - - - - 2 2 2 2 4 4 2 2 - -
Box #2 Rear-50 12 - - - - 6 4 - - - - - - - - - 2
Box #3 Left or Right-50 8 2 3 3 3 - - - - - - - - - - 1 -
Box #3 Left or Right-50 8 2 3 3 3 - - - - - - - - - - 1 -
TOTAL 40 4 6 6 6 6 4 2 2 2 2 4 4 2 2 2 2
BRICK MATRIX FOR MODEL (V)JM50 (Continued)
BRICK MATRIX Q R S T U V W X Y Z AA AB AC AD
Box #1 Hearth-50 - - - - - - - - - - - - - -
Box #2 Rear-50 3 - - - - - - - - - - - - -
Box #3 Left or Right-50 1 1 - - - - - - - - - - - -
Box #3 Left or Right-50 1 1 - - - - - - - - - - - -
TOTAL 5 2 0 0 0 0 0 0 0 0 0 0 0 0
BRICK MATRIX - (V)JM50
BRICK MATRIX FOR MODEL (V)JM50 (Continued)
BRICK MATRIX AR AS AT TOTAL
Box #1 Hearth-50 - - - 32
Box #2 Rear-50 - - - 32
Box #3 Left or Right-50 - - - 25
Box #3 Left or Right-50 - - 1 25
TOTAL 0 0 1 114
BRICK MATRIX FOR MODEL (V)JM50 (Continued)
BRICK MATRIX AE AF AG AH AI AJ AK AL AM AN AO AP AQ
Box #1 Hearth-50 - - - - - - - - - - - - -
Box #2 Rear-50 - - - - - - - 3 - - - 2 -
Box #3 Left or Right-50 - - - - - - - - - 1 1 - -
Box #3 Left or Right-50 - - - - - - - - - - 1 - -
TOTAL 0000000301220

www.desatech.com
117541-01A 19
BRICK INSTALLATION
Continued
INSTALLING Z-SHAPED GRATE
RETAINER BRACKET
Before grouting the bricks, locate the z-shaped
grate retainer brackets on top of the hearth bricks
as shown in Figure. Position the retainer brackets
at 8 3/4" apart from center to center of notch.
Figure 22 - Installing Grate Retainer
Bracket
GROUTING INSTRUCTIONS
Material provided:
2 - 9 lb. bags of cement
2 - 9 lb. gas of sand
Material required:
1 - Piping bag
1 - Joints striker
1 - Heavy duty mixing bucket
1 - Trowel
1. Moisten brick surface with a damp sponge or a
spray bottle just prior to application. When the
bricks are wet, any excess grout mixture that
might have gotten onto the brick will easily
wipe off.
2. In a heavy duty mixing bucket, pour seven (7)
cups of water in first, then add in 4.5 lbs. (half
of a bag) of sand and 4.5 lbs (half of a bag) of
cement. Mix together well using a power drill
with a mixing wand attachment.
3. The overall length of the piping bag should be
about 16". If the bag is longer than 16", cut
it down to size by removing the end with the
larger opening. This will make the bag easier
to handle.
4. Put 2 to 3 cups of the grout mixture into the
piping bag making sure the smaller opening
is downward and over a moist towel to avoid
spilling. Place a wet towel over the bucket
making sure it is directly on the surface of
the grout mixture. This will keep the mixture
moist and not dry out before use.
5. Begin grouting by first doing a “Filler Pass”.
This is done by filling the joint about 3/4 full
with the grout mixture. It is important to work
with 6 bricks at a time so that the grout doesn't
have time to set-up before striking.
6. Complete a “Finishing Pass” around 6 bricks
you just put the filler pass around. This is done
by slowly filling in the remainder of the joint
with a thick amount of the grout mixture. The
mixture should be a little higher than the brick
surface.
7. Using a trowel, remove the excess grout mix-
ture by moving the trowel in the direction of
the joint. The grout mixture in the joint should
now be flush with the brick surface.
8. Using a Joint Striker, force the grout mix-
ture into the joint and sweep back and forth
until the grout is smooth and round. If when
pressing the grout into the joint it becomes
too shallow, add more grout mixture with the
piping bag and then strike again.
9. Continue the procedure around each group of
6 bricks until an entire panel is finished.
10. Using the trowel, scrape in the direction of
the joints to remove any grout that may have
collected around the bricks during striking.
If desired, take a moist sponge and lightly
sweep over the bricks to remove any grout
that may have gotten on the bricks. DO NO
PRESS HARD OR RUB IN A CIRCULAR
MOTION. This will press the grout into the
brick and turn the brick a different color.
Allow 72 hours before operating
fireplace.
Figure 23 - Grouting Brick
See Chart
for Grate
Retainer
Brackets
Location
Model Distance Apart
JM50 8 3/4" Centers
JM42 4 1/4" Centers
JM36 3 1/4" Centers

www.desatech.com 117541-01A
20
GLASS DOOR
INSTALLATION
IMPORTANT: Install glass door
frame first before installing
glass door.
DOOR FRAME ASSEMBLY
Inset L-shaped gussets starting at the left top
portion of door frame. Gusset holes should align
with screw holes on the frame. Secure using flat
head screws.
Figure 24 - Assembling Door Frame
INSTALLING DOOR FRAME
To install glass door frame, construct an opening
(see table) on the front face of the fireplace. Insert
door frame into face opening and tighten screws
(see Figure 25).
MODEL A B
JM50 51" +/- 1/4" 34" +/- 1/4"
JM42 43" +/- 1/4" 34" +/- 1/4"
JM36 37" +/- 1/4" 34" +/- 1/4"
Figure 25 - Installing Door Frame
1" Cap Screw
Left and Right
3/4" Cap Screw
Top and Bottom
A
B
L-Shaped Gusset
Flat Head Screw
INSTALLING GLASS DOORS
Spring clips have been installed but some adjust-
ments may be needed. Install the doors using the
following steps:
1. With bi-fold doors completely folded, insert
bottom pivot pin into pivot hole located near
bottom corner of front face opening and swing
door to vertical position making sure top pins
slide into door track. Door is installed when
top door pin snaps into spring clip.
2. Repeat step 1 for remaining door.
If you find the doors do not close properly or do
not appear level or straight, proceed with section
on door adjustment,
Figure 26 - Installing Bi-Fold Doors
Spring
Clip
Insert Pin
into Spring
Clip
Pivot
Hole
Insert
Bottom
Pivot Pin
into Hole
Fold Door
and Slide
Top pins
Into Track
DOOR ADJUSTMENT
Remove doors and slightly loosen lower pivot clips
and upper spring clips. Replace doors and fully
close them. Use 1/8" shims (any material) to level
doors. Once proper setting is achieved, carefully
open doors enough so that you can access spring
clips with a phillips screwdriver. Tighten screws.
See Figure 27.
Figure 27 - Adjusting Bi-Fold Doors
Top
Bottom