Desa VRL24PR, VRL24NR, VRL24NT, VRL30NT, VRL30NR User Manual

UNVENTED (VENT-FREE) GAS LOG HEATER

OWNER’S OPERATION AND INSTALLATION MANUAL

24" AND 30" REMOTE-READY MODELS:

VRL24NR, VRL24PR, VRL30NR, VRL30PR, CSG3924NR,

CSG3924PR, CTB3924NR, CTB3924PR, CSG3930NR, CSG3930PR

24" AND 30" THERMOSTAT MODELS:

VRL24NT, VRL24PT, VRL30NT, VRL30PT, CSG3924NT, CSG3924PT,

Remote-Ready Models Also Design-Certified As Vented Decorative Appliances

CTB3924NT, CTB3924PT

WARNING: If the information in this manual is not fol­lowed exactly, a fire or explosion may result causing
property damage, personal injury or loss of life.

— Do not store or use gasoline or other flammable

vapors and 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.

Save this manual for future reference.

For more information, visit www.desatech.com

WARNING: Improper installation, adjustment, altera­tion, service or maintenance can cause injury or prop­erty damage. Refer to this manual for correct installation
and operational procedures. For assistance or addi­tional information consult a qualified installer, service
agency or the gas supplier.

WARNING: This appliance is for installation only in a
solid-fuel burning masonry or UL127 factory-built fire­place or in a listed ventless firebox enclosure. It is de­sign-certified for these installations in accordance with
ANSI Z21.11.2. Exception: Do not install this appliance
in a factory-built fireplace that includes instructions
stating it has not been tested or should not be used with
unvented gas logs.

WARNING: This is an unvented gas-fired heater. It uses
air (oxygen) from the room in which it is installed. Provi­sions for adequate combustion and ventilation air must
be provided. Refer to Air for Combustion and Ventilation
section on page 6 of this manual.

This appliance may be installed in an aftermarket,* per­manently located, manufactured (mobile) home, where
not prohibited by local codes.

This appliance is only for use with the type of gas indi­cated on the rating plate. This appliance is not convert­ible for use with other gases.

* Aftermarket: Completion of sale, not for purpose of resale, from the manufacturer

TABLE OF CONTENTS

Safety Information ............................................... 3

Product Identification ...........................................

Optional Remote Control Accessories .................

Local Codes ........................................................ 5

Unpacking ........................................................... 6

Product Features ................................................. 6

Air For Combustion and Ventilation .....................

Installation ........................................................... 8

Operating Heater ............................................... 20

Inspecting Burners ............................................ 25

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Cleaning and Maintenance ................................ 26

5

Troubleshooting .................................................

5

Optional Positioning of Thermostat Sensing Bulb

Wiring Diagram .................................................. 33

Specifications ....................................................

Illustrated Parts Breakdown .............................. 35

6

Replacement Parts ............................................ 40

Technical Service ..............................................

Service Hints ..................................................... 40

Accessories ....................................................... 41

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28

.. 32

34

40

SAFETY INFORMATION

WARNING: This product con­tains and/or generates chemicals
known to the State of California
to cause cancer or birth defects
or other reproductive harm.

IMPORTANT: Read this owner’s
manual carefully and completely
before trying to assemble, op­erate or service this fireplace.
Improper use of this fireplace
can cause serious injury or
death from burns, fire, explo­sion, electrical shock and carbon
monoxide poisoning.

DANGER: Carbon monoxide
poisoning may lead to death!

Carbon Monoxide Poiso ning: Early signs of

carbon monoxide poisoning resemble the flu, with
headaches, dizziness or nausea. If you have these
signs, the fireplace may not be working properly.
Get fresh air at once! Have fireplace serviced.
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.

Natural and Propane/LP Gas: Natural and propane/

LP gases are odorless. An odor-making agent is
added to these gases. The odor helps you detect a gas
leak. However, the odor added to the gas 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 heater or its controls can
be dangerous.

WARNING: This appliance is
for installation only in a solid-fuel
burning fireplace or approved
ventless firebox enclosure.

WARNING: Do not allow fans
to blow directly into the fireplace.
Avoid any drafts that alter burner
flame patterns. Ceiling fans can
create drafts that alter burner
flame patterns. Altered burner
patterns can cause sooting.

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 material on or near
the appliance. Never place any
objects on the heater.

Heater base assembly becomes
very hot when running heater.
Keep children and adults away
from hot surface to avoid burns
or clothing ignition. Heater
will remain hot for a time after
shutdown. Allow surface to cool
before touching.

Carefully supervise young chil­dren when they are in the room
with heater. When using the hand­held remote accessory, keep se­lector switch in the OFF position
to prevent children from turning
on burners with remote.

WARNING: Do not use a
blower insert, heat exchanger
insert or other accessory not ap­proved for use with this heater.

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You must operate this heater
with a fireplace screen in place.
Make sure fireplace screen is
closed before running heater.

SAFETY INFORMATION

Continued

Keep the appliance area clear
and free from combustible ma­terials, gasoline and other flam
mable vapors and liquids.

1. This appliance is only for use with the type of
gas indicated on the rating plate. This appliance
is not convertible for use with other gases.

2. Do not place propane/LP supply tank(s) in
side any structure. Locate propane/LP supply
tank(s) outdoors (propane/LP units only).

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 neighb orʼs phon e. Foll ow the gas
supplierʼs instructions

• if you cannot reach your gas supplier, call

the fire department

4. This heater shall not be installed in a bedroom
or bathroom unless installed as a vented appli
ance. See Installing Damper Clamp Accessory
for Vented Operation, page 13 (Remote-Ready
Models only).

5. Before installing in a solid fuel burning
fireplace, the chimney flue and firebox must
be cleaned of soot, creosote, ashes and loose
paint by a qualified chimney cleaner. Creosote
will ignite if highly heated. A dirty chimney
flue may create and distribute soot within
the house. Inspect chimney flue and firebox
for damage. If damaged, repair flue before
operating heater.

6. Do not burn solid-fuel in a masonry or UL127
factory-built fireplace in which a vent-free
room heater is installed.

7.

If fireplace has glass doors, never operate this
heater with glass doors closed. If you operate
heater with doors closed, heat buildup inside fire­place will cause glass to burst. Make sure there are
no obstructions across openings of fireplace.

8. To prevent the creation of soot, follow the
instructions in Cleaning and Maintenance,
page 26.

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9. Before using furniture polish, wax, carpet
cleaner or similar products, turn heater off. If
heated, the vapors from these products may
create a white powder residue within burner
box or on adjacent walls or furniture.

10. This heater needs fresh, outside air ventilation
to run properly. This heater has an Oxygen De
pletion Sensing (ODS) safety shutoff system.
The ODS shuts down the heater if not enough
fresh air is available. See Air for Combustion
and Ventilation, page 6. If heater keeps shutting
off, see Troubleshooting, page 28.

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11. Do not run heater

• where flammable liquids or vapors are

used or stored

• under dusty conditions

12. Do not use this heater to cook food or burn
paper or other objects.

13. Do not use heater if any part has been exposed
to or under water. Immediately call a qualified
service technician to inspect the room heater
and to replace any part of the control system and
any gas control which has been under water.

14. Do not operate heater if any log is broken. Do
not operate heater if a log is chipped (dime­sized or larger).

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15. Turn heater off and let cool before servicing,
installing or repairing. Make sure the selector
switch is in the OFF position (Remote-Ready
Models Only). Only a qualified service person
should install, service or repair heater.

16. Make sure the selector switch is in the OFF
position when you are away from home for long
periods of time (Remote-Ready Models Only).

17. Remote-ready heaters do not need to be con
nected to any external electrical source.

18. Operating heater above elevations of 4,500
feet could cause pilot outage.

19. To prevent performance problems with pro
pane/LP models, do not use propane/LP fuel
tank of less than 100 lb. capacity.

20. Prov ide adeq ua te clearan ce s around air
openings.

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110021-01M

PRODUCT

IDENTIFICATION

Log Set (Varies
According to Model)

Grate

Piezo
Ignitor

Selector Switch
(Optional)

ON/OFF/
PILOT
Knob

Burner
Control
Knob

Front and Rear
Burner Control Knob

Thermostat Models

Pilot

Grate

Piezo
Ignitor

Remote Control
(Optional)

Remote-Ready Models

Figure 1 - Product Identification

Assembly

Front
Burner

Middle
Burner

Base
Assembly

Rear
Burner

Base
Assembly

Front and Rear
Burner Control
Knob

OPTIONAL REMOTE

CONTROL ACCESSORIES

There are four optional remote controls that
can be purchased separately for Remote-Ready
Models Only:

• wall switch • hand-held ON/OFF remote

• wall thermostat • hand-held thermostat remote

See Accessories, page 41.

The wall thermostat or hand-held thermostat
may not be used where vented decorative listing
is required.

LOCAL CODES

Install and use heater with care. Follow all local
codes. In the absence of local codes, use the lat
est edition of The National Fuel Gas Code ANSI

Z223/NFPA 54*.

*Available from:

American National Standards Institute, Inc.

National Fire Protection Association, Inc.

Note: Where listed vented decorative logs are
required, thermostat models are not permitted.

State of Massachusetts: The installa­tion must be made by a licensed plumber
or gas fitt er in the Common we alth of
Massachusetts.

Sel lers of unvented propane or natural
gas-fired supplemental room heaters shall
provide to each purchaser a copy of 527
CMR 30 upon sale of the unit.

Vent-free gas products are prohibited for
bedroom and bathroom installation in the
Commonwealth of Massachusetts.

1430 Broadway

New York, NY 10018

Batterymarch Park

Quincy, MA 02269

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UNPACKING

CAUTION: Do not remove the
data plates from the grate as­sembly. The data plates contain
important warranty and safety
information.

1. Remove logs and heater base assembly from

carton. Note: Do not pick up heater base as­sembly by burners. This could damage heater.
Always handle base assembly by the sides of
assembly.

2. Remove all protective packaging applied to
logs and heater for shipment.

3. Check all items for any shipping damage. If
damaged, promptly inform dealer where you
bought heater.

PRODUCT FEATURES

OPERATION

This heater is clean burning. It requires no outside
venting. There is no heat loss out a vent or up a
chimney. Heat is generated by both realistic flames
and glowing coals. This heater is designed for vent­free operation with flue damper closed. It has been
tested and approved to ANSI Z21.11.2 standard for
unvented heaters. State and local codes in some
areas prohibit the use of vent-free heaters. This
heater may also be operated as a vented decorative
(ANSI Z21.60) product by opening the flue damper
(Remote-Ready Models Only).

SAFETY DEVICE

This heater has a pilot with an Oxygen Deple­tion Sensing (ODS) safety shutoff system. The
ODS/pilot is a required feature for vent-free room
heaters. The ODS/pilot shuts off the heater if there
is not enough fresh air.

PIEZO IGNITION SYSTEM

This heater has a piezo ignitor. This system re­quires no matches, batteries or other sources to
light heater.

AIR FOR COMBUSTION

AND VENTILATION

WARNING: This heater shall
not be installed in a confined
space or unusually tight con­struction unless provisions are
provided for adequate combus­tion and ventilation air. Read the
following instructions to insure
proper fresh air for this and
other fuel-burning appliances
in your home.

Todayʼs homes are built more energy efficient
than ever. New materials, increased insulation and
new construction methods help reduce heat loss
in homes. Home owners weather strip and caulk
around windows and doors to keep the cold air out
and the warm air in. During heating months, home
owners want their homes as airtight as possible.

While it is good to make your home energy effi
cient, your home needs to breathe. Fresh air must
enter your home. All fuel-burning appliances need
fresh air for proper combustion and ventilation.

Exhaust fans, fireplaces, clothes dryers and fuel
burning appliances draw air from the house to
operate. You must provide adequate fresh air for
these appliances. This will insure proper venting
of vented fuel-burning appliances.

PROVIDING ADEQUATE
VENTILATION

The following are excerpts from National Fuel
Gas Code. ANSI Z223.1/NFPA 54, Section 5.3,
Air for Combustion and Ventilation.

All spaces in homes fall into one of the three fol
lowing ventilation classifications:

1. Unusually Tight Construction

2. Unconfined Space

3. Confined Space

The information on pages 6 through 8 will help
you classify your space and provide adequate
ventilation.

Unusually Tight Construction

The air that leaks around doors and windows
may provide enough fresh air for combustion and
ventilation. However, in buildings of unusually
tight construction, you must provide additional
fresh air.

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110021-01M

AIR FOR COMBUSTION

AND VENTILATION

Continued

Unusually tight construction is defined as
construction where:

a. walls and ceilings exposed to the out

side atmosphere have a continuous
water vapor retarder with a rating of
one perm (6x10
less with openings gasketed or sealed
and

b. weather stripping has been added on

openable windows and doors and

c. caulking or sealants are applied to

areas such as joints around window
and door frames, between sole plates
and floors, between wall-ceiling joints,
between wall panels, at penetrations
for plumbing, electrical and gas lines
and at other openings.

If your home meets all of the three criteria
above, you must provide additional fresh air.
See Ventilation Air From Outdoors, page 8.

If your home does not meet all of the three
criteria above, proceed to Determining
Fresh-Air Flow For Heater Location.

Confined Space and Unconfined Space

The National Fuel Gas Code ANSI Z223.1/NFPA
54 defines a confined space as a space whose

volume is less than 50 cubic feet per 1,000 Btu
per hour (4.8 m
rating of all appliances installed in that space and
an unconfined space as a space whose volume is
not less than 50 cubic feet per 1,000 Btu per hour
(4.8 m3 per kw) of the aggregate input rating of
all appliances installed in that space. Rooms com­municating directly with the space in which the
appliances are installed*, through openings not
furnished with doors, are considered a part of the
unconfined space.

* Adjoining rooms are communicating only if
there are doorless passageways or ventilation grills
between them.

DETERMINING FRESH-AIR FLOW
FOR FIREPLACE LOCATION

Determining if You Have a Confined or
Unconfined Space

Use this work sheet to determine if you have a
confined or unconfined space.

Space: Includes the room in which you will install
fireplace plus any adjoining rooms with doorless pas­sageways or ventilation grills between the rooms.

-11

kg per pa-sec-m2) or

3

per kw) of the aggregate input

1. Determine the volume of the space (length x
width x height).

Length x Width x Height =__________cu. ft.

(volume of space)

Example: Space size 20 ft. (length) x 16 ft.

(width) x 8 ft. (ceiling height) = 2,560 cu. ft.
(volume of space)

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If additional ventilation to adjoining room is

supplied with grills or openings, add the volume
of these rooms to the total volume of the space.

2. Multiply the space volume by 20 to determine
the maximum Btu/Hr the space can support.

__________ (volume of space) x 20 = (Maxi-

mum Btu/Hr the space can support)

Example: 2,560 cu. ft. (volume of space) x 20 =

51,200 (maximum Btu/Hr the space can support)

3. Add the Btu/Hr of all fuel burning appliances in
the space.

Vent-free fireplace

Gas water heater*

Gas furnace

Vented gas heater

Gas fireplace logs

Other gas appliances* +

Total =

* Do not include direct-vent gas appliances. Di

rect-vent draws combustion air from the outdoors
and vents to the outdoors.

Example:

Gas water heater

Vent-free fireplace +

Total =

4. Compare the maximum Btu/Hr the space can
support with the actual amount of Btu/Hr used.

_________

_________
Example: 51,200 Btu/Hr (maximum the space

79,000 Btu/Hr (actual amount of

The space in the example is a confined space because
the actual Btu/Hr used is more than the maximum
Btu/Hr the space can support. You must provide ad
ditional fresh air. Your options are as follows:

A. Rework worksheet, adding the space of an adjoin

ing room. If the extra space provides an unconfined
space, remove door to adjoining room or add
ventilation grills between rooms. See Ventilation
Air From Inside Building, page 8.

B. Vent room directly to the outdoors. See Ventila

tion Air From Outdoors, page 8.

C. Install a lower Btu/Hr fireplace, if lower Btu/Hr

size makes room unconfined.

Btu/Hr (maximum the space can support)

Btu/Hr (actual amount of Btu/Hr used)

can support)

Btu/Hr used)

__________ Btu/Hr

__________ Btu/Hr

__________ Btu/Hr

__________ Btu/Hr

__________ Btu/Hr

__________ Btu/Hr

__________ Btu/Hr

40,000

__________ Btu/Hr

31,500

__________ Btu/Hr

71,500

__________ Btu/Hr

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AIR FOR COMBUSTION

Outlet
Air

Ventilated
Attic

Outlet

A

ir

Inlet
Air

Inlet Air

Ve

ntilated

Crawl Space

To

Crawl

Space

To Attic

Or

Remove
Door into
Adjoining

Room,
Option

3

Ventilation Grills

Into Adjoining Room,

Option

2

Ve

ntilation
Grills

Into Adjoining

Room,

Option 1

12"

12"

AND VENTILATION

Continued

If the actual Btu/Hr used is less than the maximum
Btu/Hr the space can support, the space is an un­confined space. You will need no additional fresh
air ventilation.

WARNING: If the area in
which the heater may be oper­ated is smaller than that defined
as an unconfined space or if the
building is of unusually tight
construction, provide adequate
combustion and ventilation air
by one of the methods described
in the National Fuel Gas Code,
ANSI Z223.1/NFPA 54 Section 5.3
or applicable local codes.

VENTILATION AIR

Ventilation Air From Inside Building

This fresh air would come from an adjoining un­confined space. When ventilating to an adjoining
unconfined space, you must provide two perma­nent openings: one within 12" of the ceiling and
one within 12" of the floor on the wall connecting
the two spaces (see options 1 and 2, Figure 2). You
can also remove door into adjoining room (see
option 3, Figure 2). Follow the National Fuel Gas

Code ANSI Z223.1/NFPA 54, Section 5.3, Air for
Combustion and Ventilation for required size of

ventilation grills or ducts.

Ventilation Air From Outdoors

Provide extra fresh air by using ventilation grills or
ducts. You must provide two permanent openings:
one within 12" of the ceiling and one within 12"
of the floor. Connect these items directly to the
outdoors or spaces open to the outdoors. These
spaces include attics and crawl spaces. Follow the

National Fuel Gas Code ANSI Z223.1/NFPA 54,
Section 5.3, Air for Combustion and Ventilation for

required size of ventilation grills or ducts.
IMPORTANT: Do not provide openings for inlet

or outlet air into attic if attic has a thermostat­controlled power vent. Heated air entering the attic
will activate the power vent.

Figure 3 - Ventilation Air from Outdoors

INSTALLATION

NOTICE: This heater is intended
for use as supplemental heat.
Use this heater along with your
primary heating system. Do not
install this heater as your pri­mary heat source. If you have a
central heating system, you may
run system’s circulating blower
while using heater. This will help
circulate the heat throughout the
house. In the event of a power
outage, you can use this heater
as your primary heat source.

Figure 2 - Ventilation Air from Inside

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110021-01M

INSTALLATION

Continued

WARNING: Installation and
repair should be done by a quali
fied service person. The appliance
should be inspected before use and
at least annually by a professional
service person. More frequent
cleaning may be required due to
excessive lint from carpeting, bed­ding material, etc. It is imperative
that control compartments, burners
and circulating air passageways of
the appliance be kept clean.

WARNING: Never install the

heater

• in a bedroom or bathroom

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unless installed as a vented
appliance, see page 13 (Re­mote-Ready Models Only)

• in a recreational vehicle

• where curtains, f urni ture,
clothing or other flammable
objects are less than 42 inches
from the front, top or sides of
the firebox opening

• in high traffic areas

• in windy or drafty areas

NOTICE: State or local codes may
only allow operation of this appli
ance in a vented configuration.
Check your state or local codes
(Remote-Ready Models Only).

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CAUTION: This heater cre­ates warm air currents. These
currents move heat to wall sur­faces next to heater. Installing
heater next to vinyl or cloth wall
coverings or operating heater

WARNING: Make sure the
selector switch is in the OFF
position before installing heater
(Remote-Ready Models Only).

WARNING: Before installing
in a solid fuel burning fireplace,
the chimney flue and firebox
must be cleaned of soot, creo
sote, ashes and loose paint by a
qualified chimney cleaner. Creo
sote will ignite if highly heated. A
dirty chimney flue may create and
distribute soot within the house.
Inspect chimney flue and firebox

where impurities (such as, but
not limited to, tobacco smoke,
aromatic candles, cleaning flu­ids, oil or kerosene lamps, etc.) in
the air exist, may discolor walls
or cause odors.

IMPORTANT: Vent-free heaters add moisture to
the air. Although this is beneficial, installing heater
in rooms without enough ventilation air may cause

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mildew to form from too much moisture. See Air
for Combustion and Ventilation

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CHECK GAS TYPE

Use only the correct gas type (natural or pro­pane/LP) for your unit. If your gas supply is not
correct, do not install heater. Call dealer where
you bought heater for proper type heater.

, page 6.

for damage. If damaged, repair
flue before operating heater.

WARNING: This appliance

is equipped for (natural or pro-

WARNING: Seal any fresh
air vents or ash clean-out doors

pane/LP) gas. Field conversion
is not permitted.

located on floor or wall of fire­place. If not, drafting may cause
pilot outage or sooting. Use a
heat-resistant sealant. Do not
seal chimney flue damper.

110021-01M 9

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INSTALLATION

Continued

INSTALLATION AND CLEARANCES
(Vent-Free Operation Only)

WARNING: Maintain the
minimum clearances. If you can,
provide greater clearances from
floor, ceiling and adjoining wall.

LOG SIZING REQUIREMENTS

Minimum Firebox Size
Log Front Rear

Size Height Depth Width Width*

24" 17" 14" 28" 20
30" 17" 14" 34" 22

*Measured at 14" Depth

Carefully follow the instructions below. This will
ensure safe installation into a masonry, UL127­listed manufactured fireplace or certified vent-free
firebox.

Minimum Clearances For Side
Combustible Material, Side Wall and
Ceiling

A. Clearances from the side of the fireplace

cabinet to any combustible material and wall
should follow diagram in Figure 4.

Example: The face of a mantel, bookshelf,

etc. is made of combustible material and
protrudes 3 1/2" from the wall. This combus­tible material must be 4" from the side of the
fireplace cabinet (see Figure 4).

Note: When installing your gas logs into

a man uf actur ed fireb ox , foll ow fir ebox
manufacturerʼs instructions for minimum
clearances to combustible materials.

B. Clearances from the top of the fireplace

opening to the ceiling should not be less
than 42 inches.

Example

1

/4"

3

/8"

*

NOTICE: Manual control heaters
may be used as a vented product.
If so, you must always run heater
with chimney flue damper open.
If running heater with damper
open, noncombustible material
above fireplace opening is not
needed. Go to Installing Damper

Clamp Accessory for Vented
Operation, page 13.

Minimum Noncombustible Material
Clearances

If Not Using Mantel

Note: If using a mantel, proceed to If Using
Mantel below. If not using a mantel, follow the

information below.

You must have noncombustible material(s) above
the fireplace opening. Noncombustible materials
(such as slate, marble, tile, etc.) must be at least
1/2 inch thick. With sheet metal, you must have
noncombustible material behind it. Noncom
bustible material must extend at least 8" up. If
noncombustible material is less than 12", you must
install the fireplace hood accessory. See Figure 5,
page 11, for minimum clearances.

IMPORTANT: If you cannot meet these minimum
clearances, you must operate heater with chimney
flue damper open. Go to Installing Damper Clamp

Accessory for Vented Operation

If Using Mantel

You must have noncombustible material(s) above
the fireplace opening. Noncombustible materials
(such as slate, marble, tile, etc.) must be at least
1/2 inch thick. With sheet metal, you must have
noncombustible material behind it. Noncombustible
material must extend at least 8 inches up (for all
models). If noncombustible material is less than
12", you must install the fireplace hood accessory
(24" model only). Even if noncombustible material
is more than 12", you may need the hood accessory
to deflect heat away from your mantel shelf. See
Figures 5 and 6, page 11 and Figure 7 page 12,
for minimum clearances.

IMPORTANT: If you cannot meet these minimum
clearances, you must operate heater with chimney
flue damper open. Go to Installing Damper Clamp

Accessory for Vented Operation,

, page 13.

page 13.

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*Minimum 16 inches from Side Wall

Figure 4 - Minimum Clearance for

Combustible to Wall

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110021-01M

INSTALLATION

Minimum Non­Combustible
Material

Minimum Non­Combustible
Material Height

Distances to
Underside of
Mantel

Top of Fireplace
Opening

Underside of
Mantel Shelf

Mantel Shelf

12"

(A)

18"

20"

22"

24"

All minimum
distances are
in inches

Log Set

All Models

2

1

/2

"

6"

8"

10"

Continued

Noncombustible Requirements for
Material Distance (A) Safe Installation

12" or more Noncombustible material okay.
Between 8" Install fireplace hood and 12"

accessory (GA6050, GA6052 or
GA6053, see Accessories, page 41).

Less than 8" Noncombustible material must be
extended to at least 8". See
Between 8" and 12", above. If you
cannot extend material, you must
operate heater with flue damper open.

Figure 5 - Heat Resistant Material (Slate, Marble, Tile, etc.) Above Fireplace

MANTEL CLEARANCES

In addition to meeting noncombustible material
clearances, you must also meet required clearances
between fireplace opening and mantel shelf. If
you do not meet the clearances listed below, you
will need a hood.

Determining Minimum Mantel Clearance

If you meet minimum clearance between mantel
shelf and top of fireplace opening, a hood is not
required (see Figure 6).

Figure 6 - Minimum Mantel Clearances Without Using Hood

110021-01M 11

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Minimum
Noncombustible
Material

8"
Min.

12"

15"

18"

All minimum
distances are
in inches

20"

2

1

/2"

6"

8"

10"

12"

Distances to
Underside of
Mantel

Hood
(GA6050,
GA6052 or
GA6053)

Top of
Fireplace
Opening

Underside
of Mantel
Shelf

Mantel Shelf

INSTALLATION

Hearth

5"
Min.

Combustible
Material

14"
Min.

Combustible
Material

Noncombustible Material

Continued

Determining Minimum Mantel Clearance
when Using a Hood

If minimum clearances in Figure 6 (page 11) are
not met, you must have a hood. When using a hood
there are still certain minimum mantel clearances
required. Follow minimum clearances shown in
Figure 7 when using a hood.

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.

NOTICE: If your installation does
not meet the minimum clear­ances shown, you must do one
of the following:

• operate the logs only with the
flue damper open

• raise the mantel to an accept­able height

• remove the mantel

FLOOR CLEARANCES

A. If installing appliance on the floor level, you

must maintain the minimum distance of 14"
to combustibles (see Figure 8).

B. If combustible materials are less than 14" to

the fireplace, you must install appliance at
least 5" above the combustible flooring (see
Figure 9).

Figure 8 - Minimum Fireplace Clearances

12

If Installed at Floor Level

Figure 7 - Minimum Mantel Clearances When Using Hood

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Figure 9 - Minimum Fireplace Clearances

Above Combustible Flooring

110021-01M

INSTALLATION

Continued

INSTALLING DAMPER CLAMP
ACCESSORY FOR VENTED
OPERATION

Note: When used as a vented heater, appliance
must be installed only in a solid-fuel burning
fireplace with a working flue and constructed of
noncombustible material.

If your heater is a manually-controlled model, you
may use this heater as a vented product. There
are three reasons for operating your heater in the
vented mode.

1. The fireplace does not meet the clearance
to combustibles requirements for vent-free
operation.

2. State or local codes do not permit vent-free
operation.

3. You prefer vented operation.

If reasons number 1 or 2 above apply to you, you
must permanently open chimney flue damper. You
must install the damper clamp accessory (to order,

Accessories, page 41). This will insure vented

see
operation (see Figure 10). The damper clamp will
keep damper open. Installation instructions are
included with clamp accessory.

See chart below for minimum permanent flue
opening you must provide. Attach damper clamp
so the minimum permanent flue opening will be
maintained at all times.

Area of Various Standard Round Flues

Diameter (ins.) Area (sq. ins.)

5" 20 sq. inches
6" 29 sq. inches
7" 39 sq. inches
8" 51 sq. inches

(Remote-Ready Models Only)

Damper

Damper
Clamp

Damper

Masonry Fireplace

Figure 10 - Attaching Damper Clamp

Manufactured

Damper

Fireplace

INSTALLING HEATER BASE
ASSEMBLY

CAUTION: Do not remove the
data plates attached to the heater
base assembly. The data plates
contain important warranty and
safety information.

WARNING: If installing in a
sunken fireplace, special care
is needed. You must raise the
fireplace floor to allow access to
heater control panel. This will in­sure adequate air flow and guard
against sooting and controls be­ing damaged. Raise fireplace floor
with noncombustible material.
Make sure material is secure.

Chimney Minimum Permanent
Height (ft.) Flue Opening (sq. ins.)

6' to 15' 39 sq. inches
15' to 30' 29 sq. inches

CAUTION: Do not pick up
heater base assembly by the
burner. This could damage
heater. Only handle base as
sembly by grates.

110021-01M 13

www.desatech.com

-

INSTALLATION

Continued

IMPORTANT: Make sure the heater burners are
level. If heater is not level, heater will not work
properly. For thermostat models, avoid damage
to thermostat bulb. Avoid nicks or sharp bends
in thermostat bulb wire. Keep thermostat bulb
in mounting bracket until ready to mount base
to floor. See Optional Positioning Of Thermostat
Sensing Bulb, page 32.

Installation Items Needed

• hardware package (provided with heater)

• approved flexible gas hose (not provided) (if
allowed by local codes)

•

sealant (resistant to propane/LP gas, not provided)

• electric drill with 3/16" drill bit

• flathead screwdriver

1. Connect fitting to base as shown in Figure 11.

Connect approved flexible gas hose to fitting
in base (see Figure 11).

IMPORTANT: Hold gas fitting with wrench

when connecting flexible gas hose.

2.

Locate two masonry screws in hardware package.

3. Place heater base in fireplace.

4. Place logs in their proper position on heater

base (see Installing Logs, page 18).

5. Center heater base and logs front-to-back and

side-to-side in fireplace.

6. Carefully remove logs without moving heater

base.

7. Mark screw locations through one hole on each

side of the mounting bracket (see Figure 12).
If installing in a brick-bottom fireplace, mark
screw locations in mortar joint of bricks.

8. Remove heater base from fireplace. If installing

optional control accessories, do so at this time.
Follow all directions provided with accessory.

9. Drill holes at marked locations using 3/16"

drill bit.

10. Attach base assembly to fireplace floor using

two masonry screws (in hardware package).

Flexible Gas Hose
(if allowed by local
codes)

Fitting

Mounting
Flange

Masonry Screw

Figure 12 - Attaching Base Assembly to

Fireplace Floor (30" Model Shown)

CONNECTING TO GAS SUPPLY

WARNING: This appliance
requires a 1/2" NPT (National
Pipe Thread) inlet connection to
the pressure regulator.

W AR N IN G : A qua l i fi e d
service person must connect
heater to gas supply. Follow
all local codes.

CAUTION: Never connect
propane/LP heater directly to the
propane/LP supply. Propane/LP
heaters require an external regu
lator (not supplied). Install the
external regulator between the
heater and propane/LP supply.

WARNING: For natural gas
units, never connect heater to
private (non-utility) gas wells.
This gas is commonly known
as wellhead gas.

-

Figure 11 - Attaching Flexible Gas Hose

14

to Heater

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110021-01M