Desa VTN25R Original instructions

UNVENTED (VENT-FREE) INFRARED GAS HEATER
SAFETY INFORMATION AND INSTALLATION MANUAL
MODELS CTR25NR, CTR22PR, VTN25R AND VTP22R
Save this manual for future reference.
For more information, visit www.desatech.com
WARNING: If the information in this manual is not fol-
lowed 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.

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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.
WARNING: This is an unvented gas-fired heater. It uses
air (oxygen) from the room in which it is installed. Provi-
sions for adequate combustion and ventilation air must
be provided. Refer to Air for Combustion and Ventilation
section on page 5 of this manual.
This appliance may be installed in an aftermarket,* per-
manently located, manufactured (mobile) home, where
not prohibited by local codes.
This appliance is only for use with the type of gas indi-
cated on the rating plate. This appliance is not convert-
ible for use with other gases.
* Aftermarket: Completion of sale, not for purpose of resale, from the manufacturer
TABLE OF CONTENTS
Safety Information ............................................... 3
Local Codes ........................................................ 4
Product Identification ........................................... 4
Unpacking ........................................................... 4
Product Features ................................................. 4
Air For Combustion and ventilation ..................... 5
Installation ........................................................... 7
Operating Heater ............................................... 13
Inspecting Heater .............................................. 15
Cleaning and Maintenance ................................ 16
Service Hints ..................................................... 16
Technical Service .............................................. 16
Troubleshooting ................................................. 17
Illustrated Parts Breakdown .............................. 20
Parts List ........................................................... 21
Specifications .................................................... 22
Accessory .......................................................... 22
Service Publications .......................................... 22
Replacement Parts ............................................ 22
Parts Central ..................................................... 23
State of Massachusetts: The installation must be made by a licensed plumber or gas fitter in the
Commonwealth of Massachusetts.
Sellers 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 Common-
wealth of Massachusetts.

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SAFETY INFORMATION
WARNING: This product con-
tains 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 heater.
Improper use of this heater 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 Poisoning: Early signs of carbon
monoxide poisoning resemble the flu, with head-
aches, dizziness or nausea. If you have these signs,
the heater may not be working properly. Get fresh
air at once! Have heater 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 influ-
ence 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 warn-
ings. Keep this manual for reference. It is your
guide to safe and proper operation of this heater.
WARNING: Any change to
this heater or its controls can
be dangerous.
WARNING: Do not use a
blower insert, heat exchanger
insert or other accessory not ap-
proved for use with this heater.
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.
Surface of heater 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 shut-
down. Allow surface to cool
before touching.
Carefully supervise young chil-
dren when they are in the same
room with heater.
Make sure grill guard is in place
before running heater.
Keep the appliance area clear
and free from combustible ma-
terials, 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.
3. This heater shall not be installed in a bedroom
or bathroom.
4. 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 supplierʼs
instructions
• If you cannot reach your gas supplier, call
the fire department

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4
5. This heater needs fresh, outside air ventilation
to run properly. This heater has an Oxygen
Depletion 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 5.
6. Keep all air openings in front and bottom of
heater clear and free of debris. This will insure
enough air for proper combustion.
7. If heater shuts off, do not relight until you
provide fresh, outside air. If heater keeps
shutting off, have it serviced.
8. Do not run heater
• where flammable liquids or vapors are used
or stored
• under dusty conditions
9. Do not use heater if any part has been 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.
10. Turn off heater and let cool before servicing.
Only a qualified service person should service
and repair heater.
11. Operating heater above elevations of 4,500
feet (1372 m) could cause pilot outage.
12. To prevent performance problems, do not
use propane/LP fuel tank of less than 100
psi (690 kPa) capacity.
13. 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.
14. Provide adequate clearances around air
openings.
LOCAL CODES
Install and use heater with care. Follow all local
codes. In the absence of local codes, use the latest
edition of The National Fuel Gas Code, ANSI
Z223.1/NFPA 54*.
*Available from:
American National Standards Institute, Inc.
1430 Broadway
New York, NY 10018
National Fire Protection Association, Inc.
Batterymarch Park
Quincy, MA 02269
SAFETY INFORMATION
Continued
Figure 1 - Infrared Tower Heater
UNPACKING
1. Remove heater from carton.
2. Remove all protective packaging applied to
heater for shipment.
3. Check heater for any shipping damage. If
heater is damaged, promptly contact the dealer
to where you bought heater.
PRODUCT FEATURES
SAFETY DEVICE
This heater has a pilot with an Oxygen Deple-
tion 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.
IGNITION SYSTEM
This heater has an electronic ignitor to light heater
fuel supply, which requires a AAA battery.
THERMOSTATIC HEAT CONTROL
Your unit is thermostatically controlled when heat-
er and remote control are set to the proper modes.
This results in the greatest heater comfort.
PRODUCT
IDENTIFICATION
Electronic
Ignitor
Grill
Plaque
(behind
Grill)
On/Pilot/Off Knob
Manual/Auxiliary
Knob

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AIR FOR COMBUSTION
AND VENTILATION
WARNING: This heater shall
not be installed in a confined
space or unusually tight construc-
tion unless provisions are provid-
ed 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 5 through 7 will help
you classify your space and provide adequate
ventilation.
Unusually Tight Construction
The air that leaks around doors and windows
may provide enough fresh air for combustion and
ventilation. However, in buildings of unusually
tight construction, you must provide additional
fresh air.
Unusually tight construction is 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 (6 x 10-11 kg per pa-sec-m2) or
less with openings gasketed or sealed
and
b. weather stripping has been added on
openable windows and doors and
c. caulking or sealants are applied to
areas such as joints around window
and door frames, between sole plates
and 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 these three cri-
teria, you must provide additional fresh
air. See Ventilation Air From Outdoors,
page 7.
If your home does not meet all of the three
criteria above, proceed to Determining
Fresh-Air Flow For Heater Location.
Confined 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 m3 per kw) of the aggregate input 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/Hr (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 HEATER 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
heater plus any adjoining rooms with doorless pas-
sageways or ventilation grills between the rooms.

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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) = 2560 cu. ft.
(volume of space)
If additional ventilation to adjoining room is
supplied with grills or openings, add the volume
of these rooms to the total volume of the space.
2. Multiply the space volume by 20 to determine the
maximum Btu/Hr (kw) the space can support.
__________ (volume of space) x 20 = (Maxi-
mum Btu/Hr the space can support)
Example: 2560 cu. ft. (volume of space) x 20 =
51,200 (maximum Btu/Hr the space can support)
3. Add the Btu/Hr (kw) of all fuel burning appli-
ances in the space.
Vent-free heater ________ Btu/Hr (kw)
Gas water heater* ________ Btu/Hr (kw)
Gas furnace ________ Btu/Hr (kw)
Vented gas heater ________ Btu/Hr (kw)
Gas fireplace logs ________ Btu/Hr (kw)
Other gas appliances* + ________ Btu/Hr (kw)
Total = ________ Btu/Hr (kw)
* 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 ___________ Btu/Hr (kw)
Vent-free heater ___________ Btu/Hr (kw)
Total ___________ Btu/Hr (kw)
4. Compare the maximum Btu/Hr (kw) the space can
support with the actual amount of Btu/Hr (kw) used.
___________ Btu/Hr (kw) (maximum the space can support)
___________ Btu/Hr (kw) (actual amount of Btu/Hr used)
Example: 51,200 Btu/Hr (15 kw) (maximum
the space can support)
62,000 Btu/Hr (18.2 kw) (actual
amount of Btu/Hr used)
The space in the above example is a confined space
because the actual Btu/Hr (kw) used is more than the
maximum Btu/Hr (kw) the space can support. You must
provide additional 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.
B. Vent room directly to the outdoors. See Ventila-
tion Air From Outdoors, page 7.
AIR FOR COMBUSTION
AND VENTILATION
Continued
C. Install a lower Btu/Hr (kw) heater, if lower Btu/Hr
(kw) size makes room unconfined.
If the actual Btu/Hr (kw) used is less than the maxi-
mum Btu/Hr (kw) 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 un-
confined space. When ventilating to an adjoining
unconfined space, you must provide two perma-
nent openings: one within 12" (30.5 cm) of the
ceiling and one within 12" (30.5 cm) 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.
40,000 (11.7)
+ 22,000 (6.4)
= 62,000 (18.2)
Figure 2 - Ventilation Air from Inside
Building
Or
Remove
Door into
Adjoining
Room,
Option 3
Ventilation Grills
Into Adjoining Room,
Option 2
12"
12"
Ventilation
Grills
into Adjoining
Room,
Option 1
12" (30,48 cm)
12" (30,48 cm)

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Ventilation Air From Outdoors
Provide extra fresh air by using ventilation grills
or ducts. You must provide two permanent open-
ings: one within 12" (30.5 cm) of the ceiling and
one within 12" (30.5 cm) 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 thermostat-
controlled power vent. Heated air entering the attic
will activate the power vent.
AIR FOR COMBUSTION
AND VENTILATION
Continued
Figure 3 - Ventilation Air from Outdoors
Outlet
Air
Ventilated
Attic
Outlet
A
ir
Inlet
Air
Inlet Air Ventilated
Crawl Space
To
Crawl
Space
To Attic
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 pri-
mary 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.
WARNING: A qualified ser-
vice person must install heater.
Follow all local codes.
CHECK GAS TYPE
Use only the correct type of gas (natural or pro-
pane/LP). If your gas supply is not the correct gas
type, do not install heater. Call dealer where you
bought heater for proper type heater.
WARNING: This appliance
is equipped for (natural or pro-
pane/LP) gas. Field conversion
is not permitted.
INSTALLATION ITEMS
Before installing heater, make sure you have the
items listed below.
• for propane/LP gas, external regulator (supplied
by installer)
• piping (check local codes)
• sealant (resistant to propane/LP gas)
• equipment shutoff valve *
• ground joint union
• sediment trap
• tee joint
• pipe wrench
• for natural gas, test gauge connection*
* A CSA design-certified equipment shutoff valve
with 1/8" NPT tap is an acceptable alternative to
test gauge connection. The optional CSA design-
certified equipment shutoff valve can be purchased
from your dealer. See Accessory, page 22.
LOCATING HEATER
WARNING: Maintain the
minimum clearances shown
in Figure 4. If you can, provide
greater clearances from ceiling
and joining wall(s).
Heater may be installed either in a corner or along
the wall.
Figure 4 - Clearances to Combustibles
36"
(91.4 cm)
36"
(91.4 cm)
10"
(25.4 cm)
10"
(25.4 cm)

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WARNING: Never install the
heater
• in a bedroom or bathroom
• in a recreational vehicle
• where curtains, furniture,
clothing or other flammable
objects are less than 36 inches
(91.4 cm) from the front or top
of the heater or less than 10"
(25.4 cm) from sides of heater
• as a fireplace insert
• in high traffic areas
• in windy or drafty areas
CAUTION: If you install the
heater in a home garage
• heater pilot and burner must
be at least 18 inches (45.7 cm)
above floor
• locate heater where moving
vehicle will not hit it
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 where impurities
(such as, but not limited to, to-
bacco 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
mildew to form from too much moisture. See Air
for Combustion and Ventilation, page 5. If high hu-
midity is experienced, a dehumidifier may be used
to help lower the water vapor content in the air.
For convenience and efficiency, install heater
• where there is easy access for operation, inspec-
tion and service
• in coldest part of room
INSTALLATION
Continued
An optional fan kit is available from your dealer.
See Accessory, page 22. If planning to use fan,
locate heater near an electrical outlet.
INSTALLING REMOTE CONTROL
RECEIVER
Remote control receiver must be installed to oper-
ate the remote control.
1. Locate receiver bracket, two packages of
AA batteries, remote receiver and screws in
hardware bag included with your heater.
2. Remove battery cover on receiver and install
batteries as shown in Figure 5. Replace battery
cover.
3. Insert wire connector and wire through bush-
ing on the back of heater (see Figure 6).
4. Lay heater onto its side. Insert wire connector
into valve at location shown in Figure 7 page 9.
Feed extra wire from receiver into heater base.
Place heater back in upright position.
5. Attach bracket around receiver with screws
as shown in Figure 6.
REMOTE
OFF
Battery Cover
Receiver
Figure 5 - Installing Batteries in Receiver
AA Batteries
REMOTE
OFF
Figure 6 - Installing Remote Receiver
Receiver
Receiver
Bracket
Wire
Connector Bushing

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INSTALLATION
Continued
INSTALLING BATTERIES INTO
REMOTE
1. Locate hand-held remote control in hardware
bag included with your heater.
2. Remove battery cover and insert supplied batter-
ies into remote control as shown in Figure 8.
3. Replace battery cover.
ACTIVATING COMMUNICATION
BETWEEN RECEIVER AND REMOTE
CONTROL
1. Set receiver selector switch to the remote
position (see Figure 9).
2. Push the ON button on hand-held remote
control. You should hear a beep. If not, use a
dull object to push the LEARN button in the
receiver (see Figure 9). Push the ON button
on remote control once again. You may hear
a series of beeps.
If you have questions regarding the remote control
or receiver, call 1-888-672-8929.
REPLACING BATTERY IN IGNITOR
If the spark that lights the pilot lessons, you may need
to replace the battery in the ignitor. See Figure 10.
Figure 7 - Connecting Receiver Wire
Valve
Receiver Wire
Bottom View
Figure 8 - Installing Batteries in Hand-
Held Remote Control
AAA
Batteries
Battery Cover
Remote Control
REMOTE
OFF
F
TEMPSET
ON
ROOM
OFF
MODE
SET
Figure 9 - Receiver and Remote Control
Setup
ON
Button
LEARN Button (Inside)
Slide Right to
REMOTE
Figure 11 - Mounting Heater to Floor
Wood
Screw
Mounting
Hole (One
each side)
MOUNTING HEATER BASE TO
FLOOR (Where required by local codes)
1. Position heater in desired location. Mark holes
for drilling. Move heater aside.
2. For carpeted floors, make a small cut with a
sharp knife at the marked locations prior to
drilling.
3. Drill 1/8" (diameter hole, 3/4" deep. (Do not
use anchors in wood floors.)
4. For concrete floors, use 1/4" diameter concrete
drill bit. Drill 1 3/8" deep. Insert anchors com-
pletely into holes.
5. Position heater over holes. Secure to floor with
wood screws. See Figure 11.
Figure 10 - Replacing Battery in
Electronic Ignitor
AAA Battery
Negative
towards cap

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10
INSTALLATION
Continued
CONNECTING TO GAS SUPPLY
WARNING: This appliance
requires a 3/8" NPT (National
Pipe Thread) inlet connection to
the pressure regulator.
WARNING: A qualified
service person must connect
heater to gas supply. Follow all
local codes.
WARNING: For natural gas,
never connect heater to private
(non-utility) gas wells. This
gas is commonly known as
wellhead gas.
IMPORTANT: For natural gas, check gas line
pressure before connecting heater to gas line. Gas
line pressure must be no greater than 10.5 inches
(2.6 kPa) of water. If gas line pressure is higher,
heater regulator damage could occur.
CAUTION: For propane/LP
gas, never connect heater di-
rectly to the propane/LP supply.
This heater requires an external
regulator (not supplied). Install
the external regulator between the
heater and propane/LP supply.
For propane/LP gas, the installer must supply an
external regulator. The external regulator will
reduce incoming gas pressure. You must reduce
incoming gas pressure to between 11 and 14 inches
(2.7 and 3.5 kPa) of water. If you do not reduce
incoming gas pressure, heater regulator damage
could occur. Install the external regulator with
the vent pointing down as shown in Figure 12.
Pointing the vent down protects it from freezing
rain or sleet.
Figure 12 - External Regulator With Vent
Pointing Down
External
Regulator
Propane/LP
Supply Tank
Vent
Pointing
Down
CAUTION: Use only new,
black iron or steel pipe. Inter-
nally-tinned copper tubing may
be used in certain areas. Check
your local codes. Use pipe of
large enough diameter to allow
proper gas volume to heater. If
pipe is too small, undue loss of
volume will occur.
Typical Inlet Pipe Diameter
All models - 1/2" or greater
Installation must include equipment shutoff valve,
union and plugged 1/8" NPT tap. Locate NPT
tap within reach for test gauge hook up. NPT tap
must be upstream from heater (see Figure 13,
page 11).
IMPORTANT: Install an equipment shutoff valve
in an accessible location. The equipment shutoff
valve is for turning on or shutting off the gas to
the appliance.
Apply pipe joint sealant lightly to male NPT
threads. This will prevent excess sealant from
going into pipe. Excess sealant in pipe could result
in clogged heater valves.
WARNING: Use pipe joint
sealant that is resistant to liquid
petroleum (LP) gas.

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113261-01C
CHECKING GAS CONNECTIONS
WARNING: Test all gas piping
and connections, internal and
external to unit, for leaks after
installing or servicing. Correct
all leaks at once.
WARNING: Never use an open
flame to check for a leak. Apply
a noncorrosive leak detection
fluid to all joints. Bubbles form-
ing show a leak. Correct all leaks
at once.
CAUTION: For propane/LP
gas, make sure external regula-
tor has been installed between
propane/LP supply and heater.
See guidelines under Connect-
ing to Gas Supply, page 10.
PRESSURE TESTING GAS SUPPLY
PIPING SYSTEM
Test Pressures In Excess Of 1/2 PSIG
(3.5 kPa)
1. Disconnect appliance with its appliance main
gas valve (control valve) and equipment
shutoff valve from gas supply piping system.
Pressures in excess of 1/2 psig (3.5 kPa) will
damage heater regulator.
2. Cap off open end of gas pipe where equipment
shutoff valve was connected.
3. Pressurize supply piping system by either
opening propane/LP supply tank valve for
propane/LP gas or opening main gas valve
located on or near gas meter for natural gas
or using compressed air.
4. Check all joints of gas supply piping system.
Apply a noncorrosive leak detection fluid to
all joints. Bubbles forming show a leak.
5. Correct all leaks at once.
6. Reconnect heater and equipment shutoff valve to
gas supply. Check reconnected fittings for leaks.
INSTALLATION
Continued
Tee Pipe Cap
Joint Nipple
Tee Joint
Reducer
Bushing to
1/8" NPT
1/8" NPT
Plug Tap
* A CSA design-certified equipment shutoff valve
with 1/8" NPT tap is an acceptable alternative to
test gauge connection. Purchase the optional CSA
design-certified equipment shutoff valve from your
dealer. See Accessory, page 22.
Figure 13 - Gas Connection
Pressure
Regulator
Test Gauge Connection*
Heater
Cabinet
Sediment Trap
Equipment
Shutoff
Valve *
3"
(76 mm)
Min.
Natural Gas
From Gas Meter
[7" (1.8 kPa) WC to
10.5" (2.6 kPa) WC
Pressure]
Propane/LP
From External Regulator
[11" (2.7 kPa) WC to 14"
(3.5 kPa) WC Pressure]
Regulator
Bracket
Ground
Joint
Union
3/8" NPT
Pipe
Nipple
Install sediment trap in supply line as shown in
Figure 13. Locate sediment trap where it is within
reach for cleaning. Locate sediment trap where
trapped matter is not likely to freeze. A sediment
trap traps moisture and contaminants. This keeps
them from going into heater controls. If sediment
trap is not installed or is installed wrong, heater
may not run properly.
IMPORTANT: Hold the pressure regulator with
wrench when connecting it to gas piping and/or
fittings. Do not over tighten pipe connection to
regulator. The regulator body could be damaged.

www.desatech.com 113261-01C
12
INSTALLATION
Continued
Figure 16 - Checking Gas Joints for
Propane/LP Gas
Figure 14 - Equipment Shutoff Valve
Propane/LP
Supply Tank
Open
Closed
Equipment
Shutoff Valve
Figure 15 - Checking Gas Joints for
Natural Gas
Equipment
Shutoff
Valve
Gas
Meter
Thermostat Gas Valve
(Inside Heater)
Test Pressures Equal To or Less Than
1/2 PSIG (3.5 kPa)
1. Close equipment shutoff valve (see Figure 14).
2. Pressurize supply piping system by either
opening propane/LP supply tank valve for
propane/LP gas or opening main gas valve
located on or near gas meter for natural gas
or using compressed air.
3. Check all joints from gas meter for natural gas
(see Figure 15) or propane/LP supply tank for
propane/LP gas, to equipment shutoff valve
(see Figure 16). Apply a noncorrosive leak
detection fluid to all joints. Bubbles forming
show a leak.
4. Correct all leaks at once.
PRESSURE TESTING HEATER GAS
CONNECTIONS
1. Open equipment shutoff valve (see Figure 14).
2. For natural gas open main gas valve located
on or near gas meter. For propane/LP gas open
propane/LP supply tank valve.
3. Make sure control knob of heater is in the OFF
position.
4. Check all joints from equipment shutoff valve
to thermostat gas valve (see Figure 15 or 16).
Apply a noncorrosive leak detection fluid to
all joints. Bubbles forming show a leak.
5. Correct all leaks at once.
6.
Light heater (see Operating Heater, page 13).
Check all other internal joints for leaks.
7. Turn off heater (see To Turn Off Gas to Appli-
ance, page 14).
8. Replace front panel.
Equipment
Shutoff
Valve
Thermostat Gas Valve
(Inside Heater)

www.desatech.com 13113261-01C
OPERATING HEATER
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
1. STOP! Read the safety information above.
2. Make sure equipment shutoff valve is fully
open.
3. Turn pilot knob clockwise to the OFF
position.
4. Wait five 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.
5. Press in pilot knob and turn counterclock-
wise to the PILOT position. Keep
pilot knob pressed in for five (5) seconds
(see Figure 17).
Note: You may be running this heater for
the first time after hooking up to gas supply.
If so, the pilot knob may need to be pressed
in for 30 seconds or more. This will allow
air to bleed from the gas system.
• If pilot knob does not pop up when re-
leased, contact a qualified service person
or gas supplier for repairs.
6. With pilot knob pressed in, push in ignitor
button. This will light pilot. The pilot is
located at the bottom of plaque burners. If
needed, keep pressing ignitor button until
pilot lights.
Note: If pilot does not stay lit, refer to
Troubleshooting, page 17. Also contact a
qualified service person or gas supplier for
repairs. Until repairs are made, light pilot
with a match. To light pilot with a match,
see Manual Lighting Procedure, page 14.
7. Keep pilot knob pressed in for 30 seconds
after lighting pilot. After 30 seconds, release
pilot knob.
• If pilot knob does not pop up when re-
leased, contact a qualified service person
or gas supplier for repairs.
Note: If pilot goes out, repeat steps 3
through 7.
8. With the auxiliary knob in the ON posi-
tion, turn pilot knob counterclockwise
to start the heater. The main burner
should light.
Figure 18 - Pilot
Ignitor Electrode
Pilot
Burner
Thermocouple
A
U
X
O
N
A
U
X
O
N
O
F
F
P
I
L
O
T
O
N
Figure 17 - Pilot Knob In The ON Position
Electronic Ignitor
Button
Auxiliary
Knob
Pilot
Knob

www.desatech.com 113261-01C
14
F
TEMPSET
ON
ROOM
OFF
MODE
SET
OPERATING HEATER
Continued
HAND-HELD REMOTE
CONTROL OPERATION
1. Slide selector switch on remote receiver to
the REMOTE position.
2. Slightly pull and turn auxiliary knob so the
AUX is to the left and right and ON is to the
top and bottom positions.
3. Light the pilot. Follow steps 1 through 6
under Lighting Instructions, page 13.
DISPLAY
The LCD display on the remote control indi-
cates current room temperature in Fahrenheit
or Celsius. The small flame indicates burner/
valve in operation. ROOM indicates remote
is in thermo operation. TEMP appears during
manual operation. SET appears during the
time of setting the desired temperature in the
thermostatic operation.
Turns
heater
ON
Turns
heater
OFF
Changes heater
from Manual
Mode to
Thermostatic
Mode
Sets
temperature in
Thermostatic
Mode
Figure 19 - Hand-Held Remote Control Unit
SETTING FAHRENHEIT AND CELSIUS SCALE
The factory setting for temperature is Fahr-
enheit. To change this setting to Celsius, press
the ON and OFF buttons on remote at the same
time. Follow the same procedure to change from
Celsius back to Fahrenheit.
MANUAL FUNCTION
On Operation
When the ON button is pressed the appliance
flame will come on. The LCD screen will show
ON for three seconds, then default to room
temperature and the word TEMP and flame
icon will show.
Off Operation
When the OFF button is pressed the appliance
flame will shut off. The LCD screen will show
OF for three seconds, then default to room tem-
perature and the word TEMP will show.
9. With the auxiliary knob in the AUX posi-
tion, push the ON button on the remote
control. To adjust the temperature with the
remote control, follow the instructions on
page 15. When the temperature surround-
ing the remote control drops below the set
temperature, the burner should light. The
remote receiver behind the unit must be in
the REMOTE position.
CAUTION: Do not try to ad-
just heating levels by using the
equipment shutoff valve.
TO TURN OFF GAS
TO APPLIANCE
Shutting Off Heater
1. Press in and turn pilot knob clockwise
to the OFF position.
2. Unplug any electrical power to the appli-
ance if service is to be performed.
Shutting Off Burner Only (pilot stays lit)
If auxiliary knob is in AUX position, push OFF
button on remote control.
If auxiliary knob is in ON position, turn pilot
knob clockwise to the PILOT position.
THERMOSTAT
OPERATION
The thermostat used on this heater senses the
room temperature at the location of the hand-
held remote control. At times the room may
exceed the set temperature. If so, the burner will
shut off. The burner will cycle back on when
room temperature drops below the set tempera-
ture. All plaques will turn off and on.
MANUAL LIGHTING
PROCEDURE
1. Follow steps 1 through 5 under Lighting
Instructions, page 13.
2. With pilot knob pressed in, strike match.
Hold match to pilot until pilot lights.
3. Keep pilot knob pressed in for 30 seconds
after lighting pilot. After 30 seconds, release
pilot knob. Continue with step 8 under
Lighting Instructions, above.

www.desatech.com 15113261-01C
Thermocouple Pilot Burner
Pilot Burner
Thermocouple
Blue Flame
Yellow Flame
Figure 20 - Correct Pilot Flame Pattern
Figure 21 - Incorrect Pilot Flame Pattern
Figure 22 - Burner Operation
THERMOSTATIC "ROOM" FUNCTION
Setting Desired Room Temperature
This remote control system can be thermostati-
cally controlled when the remote control is in
the thermostatic mode. The word ROOM must
be displayed on the screen.
1. Press MODE button on remote control until
ROOM appears. This sets the remote to the
thermostat mode.
2. Press and hold the SET button until the
desired temperature is displayed. The
numbers will increase from 45° to 99° then
restart over at 45°. After releasing the SET
button, the set room temperature will dis-
play for 3 seconds, then default to display
the room temperature.
Changing Set Temperature
1. Follow step two under Setting Desired Room
Temperature above.
2. Press the MODE button to disengage the
thermo mode. The word ROOM does not
display when thermostatic mode is not in
operation.
INSPECTING HEATER
Check pilot flame pattern and burner flame pat-
tern often.
PILOT FLAME PATTERN
Figure 20 shows a correct pilot flame pattern.
Figure 21 shows an incorrect pilot flame pattern.
The incorrect pilot flame is not touching the
thermocouple. This will cause the thermocouple
to cool. When the thermocouple cools, the heater
will shut down.
If pilot flame pattern is incorrect, as shown in
Figure 21
•
turn heater off (see To Turn Off Gas to Appliance,
page 14)
• see Troubleshooting, page 17
Note: The pilot flame on natural gas units will
have a slight curve, but flame should be blue and
have no yellow or orange color.
Correct
Flame
Pattern
Incorrect
Flame
Pattern
BURNER FLAME PATTERN
Figure 22 shows a correct and incorrect burner flame
pattern. If burner flame pattern is incorrect
• turn heater off (see To Turn Off Gas to Appli-
ance, page 14)
• see Troubleshooting, page 17
OPERATING HEATER
Continued

www.desatech.com 113261-01C
16
CLEANING AND
MAINTENANCE
WARNING: Turn off heater
and let cool before cleaning.
CAUTION: You must keep con-
trol areas, burner and circulating
air passageways of heater clean.
Inspect these areas of heater
before each use. Have heater
inspected yearly by a qualified
service person. Heater may need
more frequent cleaning due to
excessive lint from carpeting,
bedding material, pet hair, etc.
WARNING: Failure to keep
the primary air opening(s) of
the burner(s) clean may result in
sooting and property damage.
ODS/PILOT AND BURNER
Use a vacuum cleaner, pressurized air or small,
soft bristled brush to clean.
BURNER PILOT AIR INLET
The primary air inlet holes allow the proper
amount of air to mix with the gas. This provides a
clean burning flame. Keep these holes clear of dust,
dirt and lint. Clean these air inlet holes prior to each
heating season. Blocked air holes will create soot.
We recommend that you clean the unit every three
months during operation and have heater inspected
yearly by a qualified service person.
We also recommend that you keep the burner
tube and pilot assembly clean and free of dust and
dirt. To clean these parts we recommend using
compressed air no greater than 30 PSI (200 kPa).
Your local computer store, hardware store or home
center may carry compressed air in a can. You can
use a vacuum cleaner in the blow position. If using
compressed air in a can, please follow the direc-
tions on the can. If you don't follow directions on
the can, you could damage the pilot assembly.
1. Shut off the unit, including the pilot. Allow
the unit to cool for at least thirty minutes.
2. Inspect burner, pilot for dust and dirt.
3. Blow air through the ports/slots and holes in
the burner.
4. Never insert objects into the pilot tube.
Clean the pilot assembly also. A yellow tip on the
pilot flame indicates dust and dirt in the pilot as-
sembly. There is a small pilot air inlet about two
inches from where the pilot flame comes out of
the pilot assembly (see Figure 23). With the unit
off, lightly blow air through the air inlet. You may
blow through a drinking straw if compressed air
is not available.
CABINET
Air Passageways
Use a vacuum cleaner or pressurized air to
clean.
Exterior
Use a soft cloth dampened with a mild soap and
water mixture. Wipe the cabinet to remove dust.
BATTERIES
During long periods of time when the heater is
not being used, take batteries out of receiver and
ignitor. Remove exhausted batteries immediately.
Do not mix old and new batteries.
SERVICE HINTS
When Gas Pressure Is Too Low
• pilot will not stay lit
• burner will have delayed ignition
• heater will not produce specified heat
• propane/LP gas supply may be low
You may feel your gas pressure is too low. If so, con-
tact your local natural or propane/LP gas supplier.
TECHNICAL SERVICE
You may have further questions about installation,
operation or troubleshooting. If so, contact DESA
Heating Productsʼ 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 DESA Heating Productsʼ techni-
cal service web site at www.desatech.com.
Figure 23 - Pilot Air Inlet
Pilot Assembly
Pilot Air Inlet

www.desatech.com 17113261-01C
TROUBLESHOOTING
WARNING: Turn off and unplug heater and let cool before servicing.
Only a qualified service person should service and repair heater.
CAUTION: Never use a wire, needle or similar object to clean
ODS/pilot. This can damage ODS/pilot unit.
Note: All troubleshooting items are listed in order of operation.
POSSIBLE CAUSE
1. Ignitor electrode positioned
wrong
2. Ignitor electrode broken
3. Ignitor electrode not con-
nected to ignitor cable
4. Ignitor cable pinched or wet
5. Broken ignitor cable
6. Bad ignitor
7. Battery not installed, battery
power low or battery not in-
stalled correctly
1. Gas supply turned off or equip-
ment shutoff valve closed
2. Pilot knob not fully pressed in
while pressing ignitor button
3. Air in gas lines when in-
stalled
4. Depleted gas supply (propane/
LP gas)
5. ODS/pilot is clogged
6. Gas regulator setting is not
correct
REMEDY
1. Replace pilot assembly
2. Replace pilot assembly
3. Reconnect ignitor cable
4. Free ignitor cable if pinched
by any metal or tubing. Keep
ignitor cable dry
5. Replace ignitor cable
6. Replace ignitor
7. Install new alkaline battery in
electronic ignitor. Verify bat-
tery is installed correctly. See
page 9
1. Turn on gas supply or open
equipment shutoff valve
2. Turn to PILOT/IGN position.
Fully press in pilot knob while
pressing ignitor button
3. Continue holding down pilot
knob. Repeat igniting opera-
tion until air is removed
4. Contact local propane/LP gas
company
5. Clean ODS/pilot (see Cleaning
and Maintenance, page 16) or
replace ODS/pilot assembly
6. Replace gas regulator
OBSERVED PROBLEM
When ignitor button is pressed
in, there is no spark at ODS/
pilot
When ignitor button is pressed
in, there is a spark at ODS/Pilot
but no ignition

www.desatech.com 113261-01C
18
TROUBLESHOOTING
Continued
POSSIBLE CAUSE
1. Pilot knob not fully pressed in
2. Pilot knob not pressed in long
enough
3. Equipment shutoff valve not
fully open
4. Thermocouple connection
loose at control valve
5. Pilot flame not touching ther-
mocouple, which allows ther-
mocouple to cool, causing
pilot flame to go out. This
problem could be caused by
one or both of the following:
A) Low gas pressure
B) Dirty or partially clogged
ODS/pilot
6. Thermocouple damaged
7. Valve damaged
1. Burner orifice(s) is clogged
2. Inlet gas pressure is too low
1. Manifold pressure is too low
2. Burner orifice(s) is clogged
1. Burner orifice(s) is clogged or
damaged
2. Burner damaged
3. Gas regulator defective
1. Plaque damaged
2. Inlet gas pressure is too low
1. Residues from manufacturing
processes
1. Metal expanding while heating
or contracting while cooling
REMEDY
1. Press in pilot knob fully
2. After ODS/pilot lights, keep pi-
lot knob pressed in 30 seconds
3. Fully open equipment shutoff
valve
4. Hand tighten until snug, then
tighten 1/4 turn more
5. A) Contact local natural or
propane/LP gas company
B) Clean ODS/pilot (see
Cleaning and Maintenance,
page 16) or replace ODS/pilot
assembly
6. Replace pilot assembly
7. Replace valve
1. Clean burner orifice(s) (see
Cleaning and Maintenance, page
16) or replace burner orifice(s)
2. Contact local natural or pro-
pane/LP gas company
1. Contact local natural or pro-
pane/LP gas company
2. Clean burner orifice(s) (see
Cleaning and Maintenance, page
16) or replace burner orifice(s)
1. Clean burner orifice(s) (see
Cleaning and Maintenance, page
16) or replace burner orifice(s)
2. Replace burner
3. Replace gas regulator
1. Replace burner
2. Contact local natural or pro-
pane/LP gas company
1. Problem will stop after a few
hours of operation
1. This is common with most heat-
ers. If noise is excessive, contact
qualified service person
OBSERVED PROBLEM
ODS/pilot lights but flame
goes out when control knob is
released
Burner(s) does not light after
ODS/pilot is lit
Delayed ignition of burner(s)
Burner backfiring during com-
bustion
Burner plaque(s) does not glow
Slight smoke or odor during
initial operation
Heater produces a clicking/tick-
ing noise just after burner is lit
or shut off

www.desatech.com 19113261-01C
TROUBLESHOOTING
Continued
POSSIBLE CAUSE
1. Battery is not installed or bat-
ter power is low
1. When heated, vapors from
furniture polish, wax, carpet
cleaner, etc., may turn into
white powder residue
1. Heater burning vapors from
paint, hair spray, glues, etc.
See IMPORTANT statement
above
2. Low fuel supply (propane/LP
gas)
3. Gas leak. See Warning
statement at top of page
1. Not enough fresh air is avail-
able
2. Low line pressure
3. ODS/pilot is partially
clogged
1. Gas leak. See Warning
statement at top of page
2. Valve defective
1. Foreign matter between valve
and burner
2. Gas leak. See Warning
statement at top of page
1. Not enough combustion/ven-
tilation air
REMEDY
1. Replace AA batteries in receiver
and remote hand set
1. Turn heater off when using
furniture polish, wax, carpet
cleaners or similar products
1. Ventilate room. Stop using
odor causing products while
heater is running
2. Refill supply tank
3. Locate and correct all leaks
(see Checking Gas Connec-
tions, page 11)
1. Open window and/or door for
ventilation
2. Contact local natural or pro-
pane/LP gas company
3. Clean ODS/pilot (see Cleaning
and Maintenance, page 16)
1. Locate and correct all leaks
(see Checking Gas Connec-
tions, page 11)
2. Replace valve
1. Take apart gas tubing and
remove foreign matter
2. Locate and correct all leaks
(see Checking Gas Connec-
tions, page 11)
1. Refer to Fresh Air for Com-
bustion and Ventilation re-
quirements (page 5)
OBSERVED PROBLEM
Remote does not function
White powder residue forming
within burner box or on adjacent
walls or furniture
Heater produces unwanted
odors
Heater shuts off in use (ODS
operates)
Gas odor even when pilot knob
is in OFF position
Gas odor during combustion
Moisture/condensation noticed
on windows
WARNING: 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 neighbor’s phone. Fol-
low the gas supplier’s instructions.
• If you cannot reach your gas supplier, call the fire department.
IMPORTANT: Operating heater where impurities in air exist may create odors. Cleaning supplies,
paint, paint remover, cigarette smoke, cements and glues, new carpet or textiles, etc., create fumes.
These fumes may mix with combustion air and create odors.

www.desatech.com 113261-01C
20
2
3
4
5
6
14
15
16
16
16
19
18
25
26
22
24
12
13
21
20
20
7
8
9
10
31
17
34
35
36
32
33
1
11
27
28
29 30
28
23
F
TEMP
SET
ON
ROOM
OFF
MODE
SET
ILLUSTRATED PARTS BREAKDOWN
MODELS
CTR25NR, VTN25R, CTR22PR AND VTP22R