Desa The Aspen GL36STEP Quick start guide

Save this manual for future reference.
For more information, visit www.desatech.com
THE ASPEN
NATURAL GAS MODELS GL36ST AND GL36STE
PROPANE/LP GAS MODELS GL36STP AND GL36STEP
2-SIDED (SEE-THROUGH), VENTED DECORATIVE GAS APPLIANCE
OWNER’S OPERATION AND INSTALLATION MANUAL
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.
— WHAT TO DO IF YOU SMELL GAS :
• Do not try to light any appliance.
• Do not touch any electrical switch;
• Do not use any phone in your building.
• Immediately call your gas supplier from a neighbor’s
phone. Follow the gas supplier’s instructions.
• If you cannot reach your gas supplier, call the fire
department.
— Installation and service must be performed by a quali-
fied installer, service agency or the gas supplier.
WARNING: If the information in these instructions is
not followed exactly, a fire or explosion may result
causing property damage, personal injury or death.

www.desatech.com 55173-F2
WARNING: Improper installation, adjustment, altera-
tion, service or maintenance can cause injury or prop-
erty damage. Refer to this manual for correct installation
and operational procedures. For assistance or addi-
tional information consult a qualified installer, service
agency or the gas supplier.
NOT FOR USE WITH SOLID FUEL
CHECK LOCAL CODES PRIOR TO INSTALLATION
SAVE THIS BOOK
This book is valuable. In addition to instructing you on
how to install and maintain your appliance, it also con-
tains information that will enable you to obtain replace-
ment parts or optional accessory items when needed.
Keep it with your other important papers.
This appliance is only for use with the type of gas indi-
cated on the rating plate.
This appliance is not convertible for use with other
gases.
TABLE OF CONTENTS
Safety Information ............................................... 3
Dimensions .......................................................... 4
Introduction .......................................................... 5
Selecting Location ............................................... 5
Fireplace Installation ........................................... 6
Operating Fireplace ........................................... 13
Cleaning and Maintenance ................................ 15
Technical Service .............................................. 15
Specifications .................................................... 15
Wiring Diagrams ................................................ 16
Troubleshooting ................................................. 17
Replacement Parts and Accessories ................. 19
Limited 2-Year Warranty ....................... Back Page

www.desatech.com
55173-F 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, op-
erate or service this fireplace.
Improper use of this fireplace
can cause serious injury or death
from burns, fire, explosions,
electrical shock and carbon
monoxide poisoning.
DANGER: Carbon monoxide
poisoning may lead to death!
This fireplace is a vented product. This fireplace
will not produce any gas leakage into your home if
properly installed. This fireplace must be properly
installed by a qualified service person. If this unit is
not properly installed by a qualified service person,
gas leakage can occur.
Carbon Monoxide Poisoning: Early signs of
carbon monoxide poisoning resemble the flu, with
headaches, dizziness or nausea. If you have these
signs, the fireplace may not have been installed
properly. Get fresh air at once! Have fireplace
inspected and serviced by a qualified service
person. Some people are more affected by carbon
monoxide than others. These include pregnant
women, people with heart or lung disease or
anemia, those under the influence of alcohol and
those at high altitudes.
Propane/LP gas and natural gas are both odorless.
An odor-making agent is added to each of these
gases. The odor helps you detect a gas leak. How-
ever, the odor added to these gases can fade. Gas
may be present even though no odor exists.
Make certain you read and understand all warnings.
Keep this manual for reference. It is your guide to
safe and proper operation of this fireplace.
WARNING: Any change to
this fireplace or its controls can
be dangerous.
1. This appliance is only for use with the type
of gas indicated on the rating plate. This ap-
pliance is not convertible for use with other
gases.
2. For propane/LP fireplace, do not place propane/
LP supply tank(s) inside any structure. Locate
propane/LP supply tank(s) outdoors. To prevent
performance problems, do not use propane/LP
fuel tank of less than 100 lbs. capacity.
3. If you smell gas
• shut off gas supply
• do not try to light any appliance
• do not touch any electrical switch; do not
use any phone in your building
• immediately call your gas supplier from a
neighborʼs phone. Follow the gas supplier's
instructions
• if you cannot reach you gas supplier, call the
fire department.
4. Never install the fireplace
• in a recreational vehicle
• where curtains, furniture, clothing or other
flammable objects are less than 42" from
the front, top or sides of the fireplace
• in high traffic areas
• in windy or drafty areas
5. This fireplace reaches high temperatures. Keep
children and adults away from hot surfaces to
avoid burns or clothing ignition. Fireplace will
remain hot for a time after shutdown. Allow
surfaces to cool before touching.
6. Carefully supervise young children when they
are in the room with fireplace.
7. A hearth extension is not required with this
appliance. If one is installed, it is for aesthetic
purposes only and does not have to meet the
standard requirements.
8. Turn fireplace off and let cool before servicing
or repairing. Only a qualified service person
should install, service or repair this fireplace.
Have fireplace inspected annually by a quali-
fied service person.
9. You must keep control compartments, burn-
ers and circulating air passages clean. More
frequent cleaning may be needed due to ex-
cessive lint and dust from carpeting, bedding
material, etc. Turn off the gas valve and pilot
light before cleaning fireplace.
10. Have venting system inspected annually by a
qualified service person. If needed, have vent-
ing system cleaned or repaired. See Cleaning
and Maintenance, page 15.

www.desatech.com 55173-F4
11. Keep the area around your fireplace clear of
combustible materials, gasoline and other
flammable vapor and liquids. Do not run fire-
place where these are used or stored. Do not
place items such as clothing or decorations on
or around fireplace.
12. Do not use this fireplace to cook food or burn
paper or other objects.
13. Do not use any solid fuels (wood, coal, paper,
cardboard, etc.) in this fireplace. Use only the
gas type indicated on fireplace nameplate.
14. This appliance, when installed, must be electri-
cally grounded in accordance with local codes
or, in the absence of local codes, with the
National Electrical Code, ANSI/NFPA 70 or
the Canadian Electrical Code, CSA C22.1.
15. Do not obstruct the flow of combustion and
ventilation air in any way. Provide adequate
clearances around air openings into the combus-
tion chamber along with adequate accessibility
clearance for servicing and proper operation.
SAFETY INFORMATION
Continued
16. Do not install fireplace directly on carpeting,
vinyl tile or any combustible material other
than wood. The fireplace must set on a metal
or wood panel extending the full width and
depth of the fireplace.
17. Do not use fireplace if any part has been ex-
posed to or under water. Immediately call a
qualified service person to arrange for replace-
ment of the unit.
18. Do not operate fireplace if any log is broken.
19. Do not use a blower insert, heat exchanger
insert or other accessory not approved for use
with this fireplace.
20. Provide adequate clearances around air
openings.
6" O.D.
36 1/2"
42 1/2"
20 1/2"
52 1/2"
24"
21 1/4"
42 1/2"
9 1/2"
19"
4 1/2"
12"
16"
9"
13"
5 1/2"
2 1/2"
6"(152 mm)
15 1/4"
37 1/2"
1 1/2"
8"(203 mm)
7 1/2"
(2 1/2")
(483 mm)
(114 mm)
(64mm)
(406 mm)
(305 mm)
(330 mm)
(229 mm) (140 mm)
(953 mm)
(38 mm)
(610 mm)
(927 mm)
(1080 mm)
(1334 mm)
(521 mm)
(191 mm)
(64 mm)
(540 mm) (387 mm)
(1080 mm)
(241 mm)
(152 mm)
SIDE VIEW FRONT VIEW
TOP VIEW
DIMENSIONS

www.desatech.com
55173-F 5
Figure 2 - Typical Two-Sided Fireplace
Installation
INTRODUCTION
Models GL36ST/P and GL36STE/EP are decora-
tive gas appliances that use a millivolt gas control
and piezo pilot or an electronic gas control valve
with an electronic ignition system respectively.
These systems require a 6", B-type venting system
for operation.
The 6" B-type vent is not supplied by DESA.
For installation guidelines, check your B-vent
instructions.
WARNING: This gas appli-
ance must not be connected to
a chimney flue servicing a solid
fuel burning appliance.
Models GL36ST and GL36STE are smooth face
units for natural gas only. The GL36STP and
GL36STEP are smooth face units for propane/LP
gas only. To determine which type of gas your unit
is approved and tested for, check the rating plate on
the lift-out plate located inside the firebox under
the access panel.
BEFORE YOU BEGIN
Before beginning the installation of your appli-
ance, read these instructions through completely.
This DESA appliance and its approved compo-
nents are safe when installed according to this
installation manual and are operated as recom-
mended by DESA. Unless you use DESA approved
components tested for this appliance, YOU MAY
CAUSE A FIRE HAZARD!
The DESA warranty will be voided by and DESA dis-
claims any responsibility for the following actions :
A) Modification of the appliance or any of the
components manufactured by DESA unless
otherwise permitted by DESA.
B) Use of any component part not approved by
DESA in combination with this appliance.
C) Installation and/or operation in a manner other
than instructed in this manual.
D) The burning of anything other than the type of
gas approved for use in this gas appliance.
This appliance, when installed, must be electrically
grounded in accordance with local codes or, in the
absence of local codes, with the National Electri-
cal Code, ANSI/NFPA 70-1987 and the CSA C22.1
Canadian Electrical Code for Canada.
The installation must conform with local codes
or, in the absence of local codes, with the current
National Fuel Gas Code, ANSI Z223.1/NFPA 54
or with the current CAN/CGA B149 Installation
Codes for Canada.
This appliance complies with ANSI Z21.50B-1990
and CAM/CGA-2.22-M89 as a Vented Gas Ap-
pliance and is listed and tested by the Omni Test
Laboratories.
WARNING: Installation of
this appliance should be done
by a qualified service person
well trained in the installation
of such appliances. You will
also need a building permit from
your local Building and Safety
Commissioner before installing
this appliance; otherwise your
insurance company may not
cover this appliance.
NOTICE: This appliance is not
intended to be used as a primary
source of heat.
SELECTING LOCATION
To determine the safest and most efficient location
for your appliance, you must take into consider-
ation the following guidelines:
1. The location must allow for proper clearances
(see Clearances, page 6). Note: This decora-
tive appliance is not designed for outdoor
installation.
2. The location should be in a place where drafts,
air conditioning ducts, windows or doors will
not affect fireplace heat output.
3. A location that avoids the cutting of joists
or roof rafters will make installation easier.
Figure 2 shows a typical two-sided fireplace
installation.
IMPORTANT: All fireplace openings must be
located at least 3 feet from facing wall or com-
bustible material.
Existing
Side
Wall
4" From Opening to
Perpendicular Wall
Projected
Wall

www.desatech.com 55173-F6
Figure 3 - Clearances from Top View
Figure 4 - Clearances from Side View
MANTEL CLEARANCES
Woodwork, such as wood trims, mantels and other
combustible materials, should not be placed within
7" of the opening of this appliance (see Figure
5). Combustible material above the fireplace
projecting more than 1 1/2" from the applianceʼs
front face must not be less than 12" from the ap-
pliance opening.
Figure 5 - Mantel Clearances
FIREPLACE
INSTALLATION
CLEARANCES
Minimum clearances to combustibles are:
• Fireplace flanges to studs . . . . . . . . . . . . . . 0"
• Fireplace back/sides . . . . . . . . . . . . . . . . . . 1"
• Fireplace spacers to framing . . . . . . . . . . . . 0"
• Openings to perpendicular wall . . . . . . . . . 4"
• End glass to facing wall . . . . . . . . . . . . . . 12"
• Side glass to facing wall . . . . . . . . . . . . . . 36"
• Bottom of fireplace to floor or platform . . . 0"
• “B” vent surfaces . . . . . . . . . . . . . . . . . . . . 1"
• Top of fireplace opening to ceiling . . . . . . 35"
See Figures 3 and 4.
CAUTION: Do not block
required air spaces with insu-
lation or any other material. Do
not obstruct effective opening
of appliance with any type of
facing material.
In selecting a location, the following precautions
must be observed:
1. Do not connect this appliance to a chimney
system used for a solid fuel burning fire-
place.
2. Install in an area providing ventilation and
adequate combustion air.
3. Due to high temperatures, do not locate this
appliance in high traffic areas or near furniture
and draperies.
4. Never obstruct the front opening of the appli-
ance or the flow of combustion and ventilation
air. Keep control compartments accessible.
5. DO NOT locate in the vicinity where gasoline
or other flammable liquids may be stored. The
appliance area must be kept clear and free
from these combustible materials.
SELECTING LOCATION
Continued
1" (22 mm) Minimum
Clearance to Combustibles
1" (22 mm) Minimum
Clearance from Pipes
to Combustibles
4" (102 mm) Min. from the Perpendicular
Side Wall to the Fireplace Opening (Typ.)
6" O.D.
(152 mm)
19"
(483 mm)
11 3/8"
(289 mm)
22 3/4"
(578 mm)
22 1/4"
(565 mm)
35" (889 mm) Min.
to Effective Opening
to Ceiling
Doublewall
6" B-Vent
1" (25 mm) Min. Clearance
from Pipes to Combustibles
Do Not Pack Space
Between Spacer with
Any Type of Insulation
0" to
Floor
Note: Mantel clearances apply
to both sides of the applliacne.
Header
Drywall
Fireplace Top
12 1/4"
(Ref.)
6" (Ref.)
33°
12" Min.
7" Min.
to Effective
Opening
3" Nom.
1 1/2" Max.
Combustible
Materials

www.desatech.com
55173-F 7
FIREPLACE
INSTALLATION
Continued
FRAMING
Construct framing using dimensions shown if
Figures 6, 7 and 8. (Use the figure applicable to
your application.) Figure 6 shows the framing
dimensions prior to having the appliance in place.
Once the unit has been fitted, bring studs in against
nailing flanges located on the side of the appliance
making sure a 1" clearance is maintained as shown
in Figure 7.
If the fireplace is to be installed directly on carpet-
ing, tile (other than ceramic) or any combustible
material other than wood flooring the fireplace
must be installed upon a metal or wood panel
extending the full width and depth of the fireplace
(see Figure 8). The platform must be solid, flat and
fully supported.
Figure 6 - Framing Dimensions Prior to
Placing Appliance
Figure 7 - Securing Appliance with
Nailing Flanges
Figure 8 - Appliance Must Be Installed
on a Wood or Metal Panel if Being
Installed on Any Combustible Material
Other Than Wood
52 3/4"
(1340 mm)
Min.
46"
(11688 mm)
22 3/4"
(578 mm)
VENT PIPE INSTALLATION
A 6", B-1 type gas vent pipe is a double-wall, vent-
ing system (not supplied) which must be installed
during rough framing of the appliance. Any B-1
type gas vent system may be used for proper vent-
ing as long as the vent system is installed per the
vent manufacturerʼs recommendations.
DESA supplies this appliance with a tapered starter
pipe for a snug fit. Slide B-1 type vent pipe over
this starter pipe until vent pipe is fully seated.
Secure this first section of B-vent pipe by strap-
ping the connector around the vent pipe and then
tightening the strap with any 1/8" nut and bolt (see
Figure 9). Note: Visually inspect for proper vent
connection by looking inside top of appliance. If
connection does not appear to be correct, contact
your local service technician.
Figure 9 - Installing B-Vent Pipe
Nailing Flanges
1" Min. to Combustibles
Prepared Framing
Nails or Screws
As Required by Design as
Long as Ceiling Clearances
are Maintained
49" Minimum
(Diagonal)
B-1 Type
Vent (Not
Supplied)
Strap
(Fasten with
#6 Screw or
Bolt)

www.desatech.com 55173-F8
FIREPLACE
INSTALLATION
Continued
OPTIONAL OUTSIDE AIR KIT
(MODEL AK-4)
The installation of an outside air kit should be
completed during the rough framing of the fire-
place due to the nature of it's location. Outside
combustion air is accessed through a vented
crawl space.
CAUTION: Air inlet ducts
must not be terminated in an
attic space.
Avoid installing outside air eyebrow in areas where
inlet opening may be blocked by snow, bushes or
other obstacles (see Figure 10).
The maximum height for the air inlet termination
cannot exceed 3 feet below the B-vent termination
exhaust height.
Figure 10 - Outside Air Kit
Secure to Collars with Duct Tape or
Screws
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)
MILLIVOLT MODELS (GL36ST/STP)
The installation of a wall switch in this millivolt
control appliance allows you to activate the gas
control valve without the use of normal current.
CAUTION: Do not connect
this millivolt system wall switch
to a regular 120v power source!
Gas valve will be damaged be-
yond repair.
Wall Switch Installation
1. Remove the J-box cover plate from side of
applianceʼs outer surround.
2. Using the 18 ga. millivolt wire and wall switch
(both supplied), connect wiring per wiring
diagram (see Figure 11). For more detail, see
Wiring Diagrams on page 16.
Note: If any of the original 10 feet supplied wire
must be replaced, use Thermostat Millivolt Wire
18 AWG Type CL2-105 C or equivalent only.
IMPORTANT: Do not hook up to standard 120
VAC household wiring.
Figure 11 - Wall Switch Installation
O
F
P
I
L
O
T
ON
F
T
O
I
P
L
7
TPTHTP TH
Wall Switch
(Supplied)
Back View
To Thermopile
Route Millivolt Wires
(Supplied) Through
Electrical Conduit Bushing
ELECTRONIC MODELS (GL36STE/EP)
This appliance must be properly wired to standard
120v household current through the DESA-pro-
vided wall switch before its remote control unit
can be used to activate the automatic pilot ignition
(turn fireplace flames ON).
Wall Switch Installation
1. Remove the J-box cover plate from side of
applianceʼs outer surround.
2. Using the 18 ga. wires coming through strain
relief grommet on side of applianceʼs outer
wall to standard household 120 VAC current
through the wall switch provided, as shown in
Figure 12, page 9. For more detail, see Wiring
Diagrams, page 16.
Note: If any of the original 10 feet supplied wire
must be replaced, use 20 AWG electrical wire or
equivalent only.

www.desatech.com
55173-F 9
FIREPLACE
INSTALLATION
Continued
GAS SUPPLY TESTING
Note: This section is intended as a guide for quali-
fied technicians installing gas to this appliance.
CAUTION: Do not connect
appliance before pressure test-
ing gas piping. Damage to gas
valve may result and an unsafe
condition may be caused.
The appliance and its individual shut-off valve
must be disconnected from the gas supply piping
system during any pressure testing of that system at
test pressures in excess of 1/2 psig (3.5 kPa).
The appliance must be isolated from the gas sup-
ply piping system by closing its individual manual
shut-off valve during any pressure testing of the
gas supply piping system at test pressures equal
to or less than 1/2 psig (3.5 kPa).
This unit has been tested for installation at high
altitude in accordance with Canadian test stan-
dard CAN/CGA-2.17. Higher altitudes affect the
atmospheric pressure and heat valve of gaseous
fuels. When installing this unit at high altitudes,
the rated input will be lower than at sea level. The
lowered oxygen content in the air and the lowered
gas density require installation of a different size
orifice in order to achieve clean combustion of
the unit. Consult the unit data plate for the proper
high-altitude orifice size. Fill out the information
sticker attached to the unit when field converting.
See Specifications, page 15, when derating.
The gas control valve is secured to the burner pan
assembly underneath the front ledge. A 1/8" NPT
plugged tapping is provided on the gas control
valve for a test gauge connection immediately
upstream of the gas supply connection to the ap-
pliance (see Figures 13 and 14).
Figure 12 - Wiring Through Outer Surround
Figure 13 - Millivolt Control Valve
Figure 14 - Electronic Control Valve
ON/OFF
Knob
Pilot
Adjustment
Cap
Pilot Gas Line
Do Not Kink
Inlet
Pressure
Outlet
Pressure
To Main
Burner
To Pilot
Burner
EA
From
Gas
Supply
To
Main
Burner
Inlet
Pressure
Outlet
Pressure
GAS LINE HOOK-UP
WARNING: Gas line hookup
should be done by your gas
supplier or a qualified service
person.
WARNING: Before you pro-
ceed, make sure your gas supply
is OFF.
A manual shutoff valve has been included in the
applianceʼs gas supply system. You may consider
installing an extra gas shutoff valve outside the ap-
plianceʼs enclosure (check with local codes) where
it can be accessed more conveniently with a key
through a wall as shown in Figure 15, page 10.
A 30" long, 1/2" NPT SCHD 40 flexible gas line
(supplied) may be used between the incoming 1/2"
NPT black iron gas line and the fireplace regulator
(located inside the firebox, under the access plate).
The incoming gas line may be routed toward the
appliance from either the left or right hand side of
fireplace outer surround.
Common
Ground Wire
Strain Relief
Grommet

www.desatech.com 55173-F10
To install:
1. Remove gas line cover plate from applianceʼs
outer surround at the location to be used.
2. Remove insulation from inside the gas line
conduit sleeve.
3. Run gas line through sleeve.
4. Prepare incoming black iron gas line with
Teflon tape or pipe joint compound. (Check
local codes as to the use of Teflon tape.)
CAUTION: Compounds used
on threaded joints of gas piping
shall be resistant to the action
of Liquefied Petroleum (LP or
propane) and should be applied
lightly to ensure excess sealant
does not enter the gas line.
5. Connect incoming gas line to regulator. Secure
all joints tightly with wrench, but do not over
tighten. If a flexible gas line is used, take care
not to kink the connector.
6. Re-pack insulation in and around the conduit
sleeve and flexible gas line.
WARNING: All gas piping
and connections must be tested
for leaks after the installation is
completed.
After ensuring that the gas valve
is on, apply a commercial leak
detection solution to all con-
nections and joints. If bubbles
appear, leaks can be detected
and corrected.
Do not use an open flame for leak
testing and do not operate any
appliance if a leak is detected.
Typical Exterior Wall Gas
Shutoff Installation
Key
Extension
Shutoff
Valve
FIREPLACE
INSTALLATION
Continued
Figure 15 - Typical Exterior Wall Gas
Shut-Off Installation
LOG SET PLACEMENT
Carefully remove log set from packaging. Place
the two bottom logs over grate and align with pins.
Place three loose logs, or twigs, onto alignment
pins on two bottom logs (see Figure 16).
Figure 16 - Log Placement
FIREPLACE FACING
Any non-combustible material may be used for
facing (glass, tile, brick, etc.) as long as the proper
clearances are adhered to and the fireplace open-
ings are not blocked or obstructed in any way. See
Clearances, page 6, and Figure 17 on page 11.
Use only heat-resistant, noncombustible mortar
or adhesive when securing facing material to the
front of the fireplace.
Bottom Logs
Top Logs (Twigs)

www.desatech.com
55173-F 11
FIREPLACE
INSTALLATION
Continued
MANTELS
Mantels, combustible or non-combustible, may
be constructed as long as proper clearances are
observed (see Figure 2, page 6 and Clearances,
page 6).
PILOT ASSEMBLY ADJUSTMENT
The pilot assembly is factory preset for the proper
flame height. Alteration to factory settings may
have occurred during shipping. If this is the case,
some minor readjustments may be necessary and
should be done by a qualified technician.
The pilot assembly is located behind the burner
next to the rear refractory piece at the right-hand
side. The thermopile (in millivolt models) or the
sensor (in electronic models) should be engulfed
with the pilot flame approximately 3/8" to 1/2" in
order for the regulator to receive proper signal (see
Figures 18 and 19).
Figure 17 - Fireplace Facing Material
Figure 18 - Correct Pilot Flame Pattern
- Millivolt Assembly
Figure 19 - Correct Pilot Flame Pattern
- Electronic Assembly
BURNER FLAME ADJUSTMENT
The air shutter, located at the base of the main
burner tube, has been factory preset to the proper
air to bas ratio which results in a long, blue, cleaner
burning flame (see Figure 20).
If readjustment is necessary, loosen the air shut-
ter screw and rotate air shutter until proper flame
setting is achieved, retighten air shutter screw. See
Figure 20 for air shutter location.
Closing the air shutter reduces the air-to-gas mix,
resulting in a longer, yellow flame wihich produces
excessive carbon monoxide (CO) and could also
cause sooting.
Figure 20 - Air Shutter Adjustment
Noncombustible
Facing Material
Do Not
Block
Effective
Opening
"L" Shaped
Metal Support
Noncombustible
Facing Material
Burner Pan
Air Shutter
Screw
Orifice
Gas Valve
3/8" to 1/2"
1/8" to 1/4"
Pilot Burner Ignitor Flame
Sensor
Pan
Burner
3/8" to 1/2"
(10 mm - 13 mm)
1/8" (3 mm)
Ignitor
Pilot Burner
Thermopile

www.desatech.com 55173-F12
OPTIONAL GLASS DOOR
Glass doors are optional with this gas appliance (see
Replacement Parts and Accessories, page 19).
Installing Glass Door
1. Be sure top spring clip hole is aligned with
hole in fireplace frame (see Figure 21). Fit
glass door top pin into aligned holes.
2. Swing inner end of bottom clip out away from
fireplace frame. Fit door bottom pin into clip.
Push clip into frame until bottom door pin
slips into hole in frame.
3. Check door alignment. If doors do not align
with each other, use top spring clip to align.
a. Use Phillips screwdriver to loosen screw
that holds top spring clip in place.
b. Push spring clip left or right in its align-
ment slot until door is at proper angle
(aligned with opposing door). Moving
spring clip to the LEFT (your left as you
face the fireplace) moves glass doorʼs top,
inner corner UP; moving spring clip to
the RIGHT moves glass doorʼs top, inner
corner DOWN.
c. When door alignment is satisfactory, use
Phillips screwdriver to retighten spring
clip screw.
WARNING: When fireplace
is in operation, both sets of
cabinet doors on each side of the
fireplace must be either FULLY
OPEN or FULLY CLOSED. If not,
a fire hazard may be created.
Only doors certified with this appliance may be
used. When operating doors, do not slam or abuse
them. Always keep area below bottom edge of
doors clear of obstacles or debris. Do not operate
this appliance if glass doors are broken or dam-
aged. See Figure 22.
FIREPLACE
INSTALLATION
Continued
Figure 21 - Installing Glass Doors
Figure 22 - Glass Doors Shown Fully
Open
Adjustment
Clip
Adjustment
Screw
Top Slot
Under Frame
Long Pivot Pin
Bottom Pin
Bottom Slot
Adjustment Clip
Glass Doors Must be Fully Open
(as Shown) or Fully Closed when
Appliance is in Operation

www.desatech.com
55173-F 13
OPERATING FIREPLACE
MILLIVOLT MODELS
FOR YOUR SAFETY
READ BEFORE LIGHTING
WARNING: If you do not fol-
low these instructions exactly,
a fire or explosion may result
causing property damage, per-
sonal injury or loss of life.
A. This appliance has a pilot which must be
lighted by hand. When lighting the pilot,
follow these instructions exactly.
B. BEFORE LIGHTING smell all around the
appliance area for gas. Be sure to smell next
to the floor because some gas is heavier than
air and will settle on the floor.
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electric switch; do not
use any phone in your building.
• Immediately call your gas supplier
from a neighborʼs phone. Follow the
gas supplierʼs instructions.
• If you cannot reach your gas supplier,
call the fire department.
C. Use only your hand to push in or turn the
gas control knob. Never use tools. If the
knob will not push in or turn by hand, donʼt
try to repair it, call a qualified service tech-
nician or gas supplier. Force or attempted
repair may result in a fire or explosion.
D. Do not use this appliance if any part has
been under water. Immediately call a
qualified service technician to inspect the
appliance and to replace any part of the
control system and any gas control which
has been under water.
LIGHTING
INSTRUCTIONS
NOTICE: During initial operation
of new heater, burning logs will
give off a paper-burning smell.
Orange flame will also be pres-
ent. Open window to vent smell.
This will only last a few hours.
1. STOP! Read the safety information,
column 1.
2. Turn wall switch to the OFF position.
3. Turn off all electric power to the appliance.
4. Open control access panel.
5. Push in gas control knob and turn clock-
wise to the OFF position (see
Figure 23). Note: It is recommended that
you maintain the gas control knob in the
full OFF position during lengthy periods
of seasonal non usage.
6. Wait five (5) minutes to clear out any gas.
Then smell for gas, including near the floor.
If you smell gas, STOP! Follow “B” in the
safety information above. If you donʼt smell
gas, go to the next step.
7. Turn control knob counterclockwise
to the PILOT position.
8. Push in control knob all the way and hold
in. Immediately light the pilot by pressing
the red ignitor button until a flame ap-
pears. Continue to hold the control knob
in for about (1) minute after the pilot is lit.
Release knob and it will pop back up. Pilot
should remain lit. If it goes out, repeat steps
5 through 8.
• If knob does not pop up when released,
stop and immediately call your service
technician or gas supplier.
• If the pilot will not stay lit after sev-
eral tries, turn the gas control knob to
“OFF” and call your service technician
or gas supplier.
9. Turn gas control knob counterclockwise
to “ON”. Knob can be turned to
“ON” only if the control knob is popped out.
10. Replace control access panel.
11. Turn on all electric power to the appliance.
Figure 23 - Millivolt Control Valve
Position Indicator
Gas Control Knob

www.desatech.com 55173-F14
TO TURN OFF GAS
TO APPLIANCE
1. Turn off the wall switch.
2. Turn off all electric power to the appliance
if service is to be performed.
3. Remove control access panel.
4. Push in gas control knob and turn clockwise
to “OFF”. Do not force.
5. Replace control access panel.
OPERATING FIREPLACE
Continued
Figure 24 - Pilot
Thermopile
Pilot
Burner
Ignitor
ELECTRONIC MODELS
FOR YOUR SAFETY
READ BEFORE LIGHTING
WARNING: If you do not fol-
low these instructions exactly,
a fire or explosion may result
causing property damage, per-
sonal injury or loss of life.
A. This appliance has a pilot which must be
lighted by hand. When lighting the pilot,
follow these instructions exactly.
B. BEFORE LIGHTING smell all around the
appliance area for gas. Be sure to smell next
to the floor because some gas is heavier than
air and will settle on the floor.
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electric switch; do not
use any phone in your building.
• Immediately call your gas supplier
from a neighborʼs phone. Follow the
gas supplierʼs instructions.
• If you cannot reach your gas supplier,
call the fire department.
C. Use only your hand to push in or turn the
gas control knob. Never use tools. If the
knob will not push in or turn by hand, donʼt
try to repair it, call a qualified service tech-
nician or gas supplier. Force or attempted
repair may result in a fire or explosion.
D. Do not use this appliance if any part has
been under water. Immediately call a
qualified service technician to inspect the
appliance and to replace any part of the
control system and any gas control which
has been under water.
LIGHTING
INSTRUCTIONS
NOTICE: During initial operation
of new heater, burning logs will
give off a paper-burning smell.
Orange flame will also be pres-
ent. Open window to vent smell.
This will only last a few hours.
1. STOP! Read the safety information,
column 1.
2. Set the thermostat to lowest setting (if
applicable).
3. Turn off wall switch.
4. Open control access panel or louver.
5. Smell for gas, including near the floor. If you
smell gas, STOP! Follow “B” in the safety
information in column 1. If you donʼt smell
gas, go to the next step.
6. Turn the main burner wall switch to the ON
position for ignition. There will be a spark
at the electrode.
7. Replace control access panel or louver once
there is a flame at the burner.
8. If burner will not stay lit after several tries,
flip the wall switch to OFF and call your
service technician or gas supplier.
Figure 25 - Electronic Control Valve
EA
From
Gas
Supply
To
Main
Burner
Inlet
Pressure
Outlet
Pressure

www.desatech.com
55173-F 15
CLEANING AND
MAINTENANCE
WARNING: Installation and
repair should be done by a quali-
fied service person. The appli-
ance should be inspected before
each use and at least annually
by a qualified service person.
More frequent cleaning may be
required due to excessive lint
from carpeting, bedding mate-
rial, pet hair, etc. It is imperative
that the control compartments,
burners and circulating air sys-
tem be kept clean.
WARNING: The logs can be
hot. Handle only when cool.
TO TURN OFF GAS
TO APPLIANCE
1. Turn off all electric power to the appliance
if service is to be performed.
2. Remove control access panel.
3. Close the gas valve.
OPERATING FIREPLACE
Continued
Figure 26 - Pilot
WARNING: Turn off gas and
electrical power before servicing
appliance. Any safety screen
or guard removed for servicing
must be replaced prior to operat-
ing the appliance.
WARNING: Failure to keep
the primary air opening(s) of
the burner(s) clean may result in
sooting and property damage.
Keep control compartment, logs, burner and area
surrounding logs clean by vacuuming or brushing
at least twice a year. Take care not to alter the set-
tings on the pilot assembly.
Do not use abrasive liquids or cleaners for cleaning
glass doors and trims. Any household glass cleaner
should suffice. Do not clean doors when hot. Allow
appliance to cool before cleaning.
TECHNICAL SERVICE
You may have further questions about installation,
operation or troubleshooting. If so, contact DESAʼs
Technical Service Department at 1-866-672-6040.
When calling please have your model and serial
numbers of your heater ready.
You can also visit DESAʼs Technical Services web
site at www.desatech.com.
SPECIFICATIONS
GL36ST, GL36STE
• Maximum Input Rating at Altitudes: 2,000 ft.
- 42,000 Btu/hr., 2,000 ft. to 4,000 ft. - 37,800
Btu/hr.
• Manifold Pressure: 3.5 W.C. (.87 kPa)
• Supply Pressure (in. of water): Minimum* - 4.5"
(1.12 kPa), Maximum - 11.0" (2.74 kPa)
• Orifice Size at Altitudes: 2,000 ft. - #30, 2,000 ft.
to 4,000 ft. - #31
GL36STP, GL36STEP
• Maximum Input Rating at Altitudes: 2,000 ft.
- 42,000 Btu/hr., 2,000 ft. to 4,000 ft. - 37,800
Btu/hr.
• Manifold Pressure: 11.0 W.C. (2.74 kPa)
• Supply Pressure (in. of water): Minimum* -
12.0" (2.89 kPa), Maximum - 13.0" (3.23 kPa)
• Orifice Size at Altitudes: 2,000 ft. - #49, 2,000 ft.
to 4,000 ft. - #51
* For the purpose of input adjustment

www.desatech.com 55173-F16
DO NOT
CONNECT
N.C.SW
HEAT LIMIT SWITCH
TH/TP
TP
TH
WALL SWITCH
(SUPPLIED)
TO 120V
THERMOPILE
PILOT
IGNITOR
O
F
F
P
I
L
O
T
O
N
PILOT SAFETY WIRE
MAIN GAS
INCOMING
SUPPLY
MILLIVOLT WIRING DIAGRAM
STEP DOWN
TRANSFORMER
EV2
SUPPLY
INCOMING
MAIN GAS
EV1
TO
GAS LINE
BURNER
24V AC
N.C.SW
HEAT LIMIT
SWITCH
120V AC
120V AC
INCOMING
OR BREAKER)
(FUSE BOX
OFF
ON
(SUPPLIED)
WALL SWITCH
GREEN BLACK WHITE
120v, 60Hz, 0.7A
ELECTRICAL RATING:
BLACK
WHITE
GREEN
OPTIONAL
REMOTE
CONTROL
SENSOR
PILOT
IGNITOR
PV
GND
PV/MV TR
MV TH IGN
ELECTRONIC WIRING DIAGRAM
WIRING DIAGRAMS

www.desatech.com
55173-F 17
TROUBLESHOOTING
MILLIVOLT SYSTEM
Note: Before troubleshooting the system, make sure the gas shutoff valve is ON.
The two most common causes of a malfunctioning gas appliance are:
1. Loose wiring connections
2. Construction debris clogging the pilot and/or gas control valve filter
OBSERVED PROBLEM
Pilot will not light
Pilot will not stay lit
No gas to burner, although wall
switch and valve are set to the
ON position
Frequent pilot outage
Pilot goes out when wall switch
is ON
POSSIBLE CAUSE
1. No gas supply or shutoff
valve is OFF
2. Air in gas line
3. Construction debris clog-
ging pilot orifice
4. Low gas pressure
5. Control valve knob is not on
the PILOT position
6. Kinked pilot line
7. Bad valve
1. Loose wiring on thermopile
to control valve.
2. No millivolt current is being
sent back to regulator
3. If valve knob and wall switch
are in the ON position, prob-
able defective control valve
1. Wall switch wires defective
2. Thermopile or sensor not
generating sufficient voltage
1. Pilot flame may be too
low, causing safety pilot to
“drop out”
1. Millivolt output on thermo-
pile too high
REMEDY
1. Check to see if you have gas
supply
2. Hold regulator control valve
in the PILOT position for 2 to
3 minutes to purge air. If you
smell gas stop and wait for a
few minutes before trying to
light the fireplace
3. Remove debris and dirt, in-
spect and clean any other
possible obstructions
4. Contact your gas supplier
5. Refer to section on pilot
lighting
6. Have a qualified technician
replace pilot line
7. Replace control valve (see
Replacement Parts, page 19)
1. Check wiring connections.
Refer to wiring diagrams on
page 15
2. Have a qualified technician
check millivolts
3. Have a qualified technician
replace valve (see Replace-
ment Parts and Accessories,
page 19)
1. Check electrical connections
and wires for continuity
2. See Pilot will not stay lit,
above
1. Clean and adjust pilot flame
for maximum flame impinge-
ment on thermopile
1. Have a qualified technician
replace thermopile

www.desatech.com 55173-F18
TROUBLESHOOTING
ELECTRONIC IGNITION SYSTEM
Note: Before troubleshooting the system, make sure the gas shutoff valve is ON.
The two most common causes of a malfunctioning gas appliance are:
1. Loose wiring connections
2. Construction debris clogging the pilot and/or gas control valve filter
OBSERVED PROBLEM
Pilot will not light
Pilot will not stay lit
No gas to burner, although wall
switch and valve are set to the
ON position
Frequent pilot outage
Pilot goes out when wall switch
is ON
POSSIBLE CAUSE
1. No gas supply or shutoff
valve is OFF
2. Construction debris clog-
ging pilot orifice
3. Low gas pressure
4. Control valve knob is not on
the PILOT position
5. Kinked pilot line
6. Bad valve
1. Loose wiring on thermopile
to regulator valve. No mil-
livolt current is being sent
back to regulator
2. If valve knob and wall switch
are in the ON position, prob-
able defective control valve
1. Wall switch wires defective
2. Thermocouple generator or
sensor not generating suf-
ficient voltage
1. Pilot flame may be too
low, causing safety pilot to
“drop out”
1. Output on flame sensor too
high
REMEDY
1. Check to see if you have gas
supply
2. Remove debris and dirt, in-
spect and clean any other
possible obstructions
3. Contact your gas supplier
4. Refer to section on pilot
lighting
5. Have a qualified technician
replace pilot line
6. Replace control valve (see
Replacement Parts and Acces-
sories, page 19)
1. Check wiring connections.
Refer to wiring diagrams on
page 16
2. Have a qualified technician
replace valve (see Replace-
ment Parts and Accessories,
page 19)
1. Check electrical connections
and wires for continuity
2. See Pilot will not stay lit,
above
1. Clean and adjust pilot flame
for maximum flame impinge-
ment on thermopile
1. Replace flame sensor

www.desatech.com
55173-F 19
REPLACEMENT PARTS AND ACCESSORIES
Purchase these fireplace replacement parts and
accessories from your local dealer. If they can not
supply these parts, call DESA at 1-866-672-6040
for referral information. You can also write to the
address listed on the back page of this manual.
Before ordering, please have your applianceʼs
model name or number and part number of the
item(s) you are ordering ready. The model name or
number for your particular appliance may be found
on the rating label located inside the appliance.
MILLIVOLT VALVE
Natural Gas - 14512
Propane/LP Gas - 14513
ELECTRONIC VALVE
Natural Gas - 14569
Propane/LP Gas - 14570
MILLIVOLT PILOT ASSEMBLY
Natural Gas - 112784-01
Propane/LP Gas - 112784-02
ELECTRONIC PILOT ASSEMBLY
Natural Gas - 108866-01
Propane/LP Gas - 108866-02
TRANSFORMER - 14129
For use with all models.
PIEZO IGNITER - 14261
For use with all models.
ORIFICE
Natural Gas - 23105
Propane/LP Gas - 23106
For use with all models.
WALL SWITCH KIT - 22180
Wall Switch - 14112
Cover Plate - 14113
For use with all models.
IGNITION CONTROL - 110286-01
For use with all models.
GAS VALVE CONVERSION KIT
Millivolt Propane/LP Gas - PC-GL36
Millivolt Natural Gas - NC-GL36
Electronic Propane/LP Gas - PC-GL36E
Electronic Natural Gas - NC-GL36E
BRUSHED BRASS CABINET STYLE
DOOR KIT - DBBGL36ST
Right Panel Assy - 22367
Left Panel Assy - 22368
For use with all models.
BURNER ASSEMBLY - 23439
For use with all models.
REMOTE CONTROL KIT - 01026
For Millivolt Units Only - Batteries required for
receiver and transmitter.
REMOTE CONTROL KIT - 00825
For Millivolt Units Only - No batteries required
for receiver or transmitter.
REMOTE CONTROL KIT - 11710
For use with all models.
VENT HOOD - AK4
For use with all models.
REFRACTORY
Side Refractory - 23519
Bottom Refractory - 23516
Face - 112139-01
For use with all models.
GRATE ASSEMBLY - 11159
For use with all models.
LOG SET ASSEMBLY - 25793
Bottom Rear Log - 25795
Bottom Front Log - 25794
Top Left Log - 25797
Top Center Log - 25672
Top Right Log - 25796
For use with all models.
"B-1 TYPE" VENT PIPE
For use with all models. Any B-1 type, 6" diam-
eter, gas vent pipe may be purchased from your
local vent manufacturer.

2701 Industrial Drive
P.O. Box 90004
Bowling Green, KY 42102-9004
www.desatech.com
55173
Rev. F
09/05
LIMITED 2-YEAR WARRANTY
DESA warrants this gas appliance to be free from the defects in material or workmanship at the time of manufacture.
REMEDY AND EXCLUSIONS
The coverage of this warranty is limited to all components of the gas appliance manufactured by DESA, with the
exception of glass and refractory. The glass is warranted for 90 days. There will be no cost for replacement of glass
within 90 days of installation, provided that breakage is due to heat from the appliance. We do not warranty breakage
occurring during installation or transportation.
If the decorative gas appliance covered by this warranty is found to be defective within one year from the date of installation,
DESA will, at its option, replace or repair defective components of the decorative gas appliance manufactured by DESA
at no charge or will pay for reasonable costs incurred in replacing or repairing such components. These charges should be
pre-approved by DESA before any work is done. During the second year of the warranty, DESA shall supply replacement
parts, if readily available, at the current minimum wholesale price. DESA will not be responsible for any other expense.
REFRACTORY WARRANTY
FIRST YEAR: DESA warrants the refractory (except the hairline cracks less than 1/16” in width) one year from the
date of manufacture to be free from defect in material and workmanship. If the original owner of a DESA fireplace
believes that any of the refractory parts have failed during the above one year period, the current owner should notify
the nearest (DESA) distributor or dealer. DESA will pay for the refractory replacement and reasonable labor charges.
DESA will be responsible for the freight charges.
SECOND YEAR: DESA will supply the refractory replacement parts at the current list price that is in effect at time
of the replacement. DESA will assume no responsibility for any labor and freight charges incurred.
This warranty covers only parts and labor as provided above. In no case shall DESA be responsible for materials,
components or construction which are not manufactured or supplied by DESA. DESA will not be responsible for any
labor charges to remove such materials, components or construction. All replacement parts will be shipped. F.O.B.,
Santa Ana, to purchasersʼ address or the nearest DESA distributor.
QUALIFICATIONS TO THE WARRANTY
The decorative gas appliance warranty outlined above is further subject to the following qualifications:
1. The gas appliance must be installed as per the DESA installation instructions and local building codes. The use of
components manufactured by others with this DESA gas appliance (except for the Type B venting system as outlined
in the installation instructions, if applicable) could create serious safety hazards may result in denial of certification
by recognized national safety agencies and could be in violation of local building codes. This warranty does not
cover any damages occurring from the use of my components not manufactured or supplied by DESA.
2. The DESA appliance must be subjected to normal use. The decorative gas appliances are designed to burn either
natural or propane/LP gas only. Burning conventional fireplace fuels such as wood, coal or any other solid fuel will
cause damage to the decorative gas appliance, will produce excessive temperatures and will result in a fire hazard.
LIMITATION OF LIABILITY
It is expressly understood that DESAʼs sole obligation and purchaserʼs exclusive remedy under this warranty, expressed
or implied, or in contract, tort or otherwise, shall be limited to replacement or repair as specified above. In no event shall
DESA be responsible for any incidental or consequential damages caused by defects in its products, whether such dam-
age occurs or is discovered before or after replacement or repair and whether or not such damage is caused by DESAʼs
negligence. Some states do not allow the exclusion or limitation of incidental or consequential damages, so the above
limitation or exclusion may not apply to you. The duration of any implied warranty with respect to this DESA decorative
gas appliance is limited to the duration of the foregoing warranty.
INVESTIGATION OF CLAIMS AGAINST WARRANTY
DESA reserves the right to investigate any and all claims against this warranty and to decide upon method of settle-
ment. DESA is not responsible for work done without written consent. DESA shall in no event be responsible for any
warranty work done without first obtaining DESAʼs written consent.
HOW TO REGISTER A CLAIM
A (DESA) dealer or distributor should be contacted directly by the owner for any service, including service under
these warranties. The repair and replacement of any defective part covered by these warranties is the responsibility
of the nearest (DESA) dealer or distributor.
OTHER
This warranty gives you specific rights and you may also have other rights which vary from state to state,. These
warranties are given in lieu of any other expressed warranties. DESA does not authorize any person or representative
to make representations to the contrary in connection with the sale of a decorative gas appliance.
55173
NOT A UPC