Vanguard VN18TA Original instructions

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WARNING: If the information in this manual is not
followed exactly, a fire or explosion may result caus-
ing 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.
UNVENTED (VENT-FREE) INFRARED GAS HEATER
SAFETY INFORMATION AND INSTALLATION MANUAL
VN18A, VN18TA, VP16A, VP16TA, VP26A, VP26TA
VN30A, VN30TA, VP16ITA, VP22ITA
Model VN30A Shown
®

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2
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
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.
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 ............................................... 14
Inspecting Heater .............................................. 18
Cleaning and Maintenance ................................ 19
Troubleshooting ................................................. 20
Specifications .................................................... 23
Illustrated Parts Breakdown and Parts List ....... 24
Replacement Parts ............................................ 32
Service Publications .......................................... 32
Service Hints ..................................................... 32
Technical Service .............................................. 32
Accessories ....................................................... 33
Parts Central ..................................................... 33
Warranty Information ...........................Back Cover

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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 blow-
er insert, heat exchanger insert
or other accessory not approved
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 ap-
pliance 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. Always run heater with plaque control knob at the
1, 2, 3 or 4 locked positions. Never set control knob
between locked positions. Poor combustion and
higher levels of carbon monoxide may result.
6. 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.
7. Keep all air openings in front and bottom of
heater clear and free of debris. This will insure
enough air for proper combustion.
8. If heater shuts off, do not relight until you
provide fresh, outside air. If heater keeps
shutting off, have it serviced.
9. Do not run heater
• where flammable liquids or vapors are
used or stored
• under dusty conditions
10. 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.
11. Turn off and unplug heater and let cool before
servicing. Only a qualified service person
should service and repair heater.
12. Operating heater above elevations of 4,500
feet could cause pilot outage.
13. To prevent performance problems, do not use pro-
pane/LP fuel tank of less than 100 lbs. capacity.
14. 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.
15. 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 lat-
est 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
Heater Cabinet
Front Panel
Grill
Guard
Ignitor Button Control
Knob
Plaque
Figure 1 - Vent-Free Gas Heater
PRODUCT
IDENTIFICATION
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 return 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.
THERMOSTATIC HEAT CONTROL
(Thermostat Models Only)
Thermostat models have a thermostat sensing
bulb and a control valve. This results in the great-
est heater comfort. This can also result in lower
gas bills.

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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 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 per hour
(4.8 m3 per kw) of the aggregate input rating of
all appliances installed in that space. Rooms com-
municating 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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6
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 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 of all fuel burning appliances in
the space.
Vent-free heater ___________ Btu/Hr
Gas water heater* ___________ Btu/Hr
Gas furnace ___________ Btu/Hr
Vented gas heater ___________ Btu/Hr
Gas fireplace logs ___________ Btu/Hr
Other gas appliances* + ___________ Btu/Hr
Total = ___________ Btu/Hr
* 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
Vent-free heater + __________ Btu/Hr
Total = __________ Btu/Hr
4. Compare the maximum Btu/Hr the space can
support with the actual amount of Btu/Hr used.
_________ Btu/Hr (maximum the space can support)
_________ Btu/Hr (actual amount of Btu/Hr used)
Example: 51,200 Btu/Hr (maximum the space
can support)
60,000 Btu/Hr (actual amount of
Btu/Hr used)
The space in the above example is a confined space
because the actual Btu/Hr used is more than the maxi-
mum Btu/Hr 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 heater, if lower Btu/Hr size
makes room unconfined.
If the actual Btu/Hr used is less than the maximum
Btu/Hr the space can support, the space is an un-
confined space. You will need no additional fresh
air ventilation.
WARNING: If the area in
which the heater may be oper-
ated 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" 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.
40,000
20,000
60,000
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

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AIR FOR COMBUSTION
AND VENTILATION
Continued
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 thermostat-
controlled 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 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 Accessories, page 33.
LOCATING HEATER
WARNING: Maintain the
minimum clearances shown
in Figure 4. If you can, provide
greater clearances from floor,
ceiling and joining wall.
You can locate heater on the floor, away from a
wall. A wall mounting bracket and floor base stand
are included with this heater. Determine which
method is best for your application.
Figure 4 - Mounting Clearances As
Viewed From Front of Heater
Outlet
Air
Ventilated
Attic
Outlet
A
ir
Inlet
Air
Inlet Air Ventilated
Crawl Space
To
Crawl
Space
To Attic
Minimum
From
Sides Of
Heater
36"
2"
FLOOR
CEILING
Minimum
Minimum To
Top Surface
Of Carpeting,
Tile Or Other
Combustible
Material
Left
Side
Right
Side
10"

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8
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
from the front, top or sides of
the 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 above
floor
• locate heater where moving
vehicle will not hit it
CAUTION: This heater cre-
ates warm air currents. These
currents move heat to wall sur-
faces next to heater. Installing
heater next to vinyl or cloth wall
coverings or operating heater
where impurities (such as, but
not limited to, tobacco smoke,
aromatic candles, cleaning flu-
ids, 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 humidity is experienced, a dehumidi-
fier 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 Accessories, page 33. If planning to use fan,
locate heater near an electrical outlet.
THERMOSTAT SENSING BULB
(Thermostat Models Only)
The thermostat sensing bulb has been placed
below the heater.
1. Place clamp on thermostat sensing bulb as
shown in Figure 5. Clamp is provided in
hardware package.
2. Snap clamp into upper mounting hole as shown
in Figure 5. Mounting hole is located on lower
left edge on back of heater. Make sure the
thermostat sensing bulb is pointing up.
Figure 5 - Attaching Thermostat Sensing
Bulb
Clamp
Thermostat
Sensing
Bulb
INSTALLING HEATER TO WALL
Mounting Bracket
Locate mounting bracket in heater carton. Remove
mounting bracket from heater carton.
Figure 6 - Mounting Bracket
Removing Front Panel Of Heater
1. Remove the four painted screws, two on each
side of front panel.
2. Pull bottom of front panel forward, then out.
3. Remove any remaining packaging materials.
Figure 7 - Removing Front Panel Of
Heater
Screw
Front Panel

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INSTALLATION
Continued
Methods For Attaching Mounting Bracket
To Wall
Only use last hole on each end of mounting bracket
to attach bracket to wall. These two holes are 14
inches apart from their centers. Attach mounting
bracket to wall in one of two ways:
1. Attaching to wall stud
2. Attaching to wall anchor
Attaching to Wall Stud: This method provides the
strongest hold. Insert mounting screws through
mounting bracket and into wall studs.
Attaching to Wall Anchor: This method allows you
to attach mounting bracket to hollow walls (wall
areas between studs) or to solid walls (concrete
or masonry).
Decide which method better suits your needs.
Either method will provide a secure hold for the
mounting bracket.
Marking Screw Locations
1. Tape mounting bracket to wall where heater
will be located. Make sure mounting bracket
is level.
WARNING: Maintain mini-
mum clearances shown in Figure
8. If you can, provide greater
clearances from floor and join-
ing wall.
2. Mark screw locations on wall (see Figure 8).
Note: Only mark last hole on each end of
mounting bracket. Insert mounting screws
through these holes only.
3. Remove tape and mounting bracket from
wall.
4 and 5 Plaque Heaters
3 Plaque Heater
Figure 8 - Mounting Bracket Clearances
Attaching Mounting Bracket To Wall
Note: Wall anchors, mounting screws and spacers
are in hardware package. The hardware package
is provided with heater.
Attaching To Wall Stud Method
For attaching mounting bracket to wall studs
1. Drill holes at marked locations using 9/64"
drill bit.
2. Place mounting bracket onto wall. Line up last
hole on each end of bracket with holes drilled
in wall.
3. Insert mounting screws through bracket and
into wall studs.
4. Tighten screws until mounting bracket is
firmly fastened to wall studs.
Attaching To Wall Anchor Method
For attaching mounting bracket to hollow walls
(wall areas between studs) or solid walls (concrete
or masonry)
1. Drill holes at marked locations using 5/16"
drill bit. For solid walls (concrete or masonry),
drill at least 1" deep.
16"
Min.
14"
12"
Min.
Adjoining Wall
14"
Adjoining Wall
Only Insert Mounting
Screws Through Last
Hole On Each End
Only Insert Mounting
Screws Through Last
Hole On Each End
Floor Floor
25 3/4"
Optional
19 3/4"
Min.
25 3/4"
Optional
19 3/4"
Min.
16"
Min.
14"
12"
Min.
Adjoining Wall
14"
Adjoining Wall
Only Insert Mounting
Screws Through Last
Hole On Each End
Only Insert Mounting
Screws Through Last
Hole On Each End
Floor
Floor
25 3/4"
Optional
19 3/4"
Min.
25 3/4"
Optional
19 3/4"
Min.

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10
2. Fold wall anchor as shown in Figure 9.
3. Insert wall anchor (wings first) into hole. Tap
anchor flush to wall.
4. For thin walls (1/2" or less), insert red key
into wall anchor. Push red key to “pop” open
anchor wings.
IMPORTANT: Do not hammer key!
For thick walls (over 1/2" thick) or solid walls,
do not pop open wings.
5. Place mounting bracket onto wall. Line up
last hole on each end of bracket with wall
anchors.
6. Insert mounting screws through bracket and
into wall anchors.
7. Tighten screws until mounting bracket is
firmly fastened to wall.
INSTALLATION
Continued
Figure 9 - Folding Anchor
Figure 10 - Popping Open Anchor Wings
For Thin Walls
Figure 11 - Mounting Heater Onto
Mounting Bracket
Mounting
Bracket
(attached
to wall)
Horizontal Slots
Stand-Out Tab
Placing Heater On Mounting Bracket
1. Locate two horizontal slots on back panel of
heater.
2. Place heater onto mounting bracket. Slide
horizontal slots onto stand-out tabs on mount-
ing bracket.
Installing Bottom Mounting Screws
1. Locate two bottom mounting holes. These
holes are near bottom on back panel of heater
(see Figure 12).
2. Mark screw locations on wall.
3. Remove heater from mounting bracket.
4. If installing bottom mounting screws into
hollow or solid wall, install wall anchors.
Follow steps 1 through 4 under Attaching To
Wall Anchor Method, page 9.
If installing bottom mounting screw into wall
stud, drill holes at marked locations using 9/64"
drill bit.
5. Replace heater onto mounting bracket.
6. Place spacers between bottom mounting holes
and wall anchor or drilled hole.
7. Hold spacer in place with one hand. With other
hand, insert mounting screw through bottom
mounting hole and spacer. Place tip of screw
in opening of wall anchor or drilled hole.
8. Tighten both screws until heater is firmly
secured to wall. Do not over tighten.
Note: Do not replace front panel at this time.
Replace front panel after making gas connec-
tions and checking for leaks (see pages 12
and 13).
Figure 12 - Installing Bottom Mounting
Screws
Side View
Front View
Wall
Spacer
Heater

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113052-01D
INSTALLATION
Continued
MOUNTING HEATER TO FLOOR
Mounting Base Feet to Heater
1. Lay heater cabinet on its back on a table
with the heater bottom overhanging the table
edge.
2. Align holes in base foot with mounting holes
on bottom of cabinet (see Figure 13).
3. Secure base foot to heater using sheet metal
screws.
4. Repeat for other side.
Mounting Base Feet to Floor (Where
required by local code)
1. Remove front cover (see Removing Front
Panel of Heater, page 8).
2. Position heater with base feet in desired loca-
tion. Mark holes for drilling. Remove heater
with base.
3. For carpeted floors, make a small cut with a
sharp knife at marked locations prior to drill-
ing. If mounting base to a wood floor, drill 1/8
inch diameter hole, 3/4 inch deep. (Do not use
anchors in wood floors).
If mounting base to a concrete floor, drill
with 1/4 inch diameter concrete drill bit, 13/8
inches into floor. Insert anchors completely
into holes.
4. Reposition heater with base feet over holes.
Secure base to floor with wood screws. See
Figure 13.
Figure 13 - Installing Base Feet
Wood
Screw
Sheet Metal Screw
Base Foot
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 com-
monly 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 of
water. If gas line pressure is higher, heater regula-
tor 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
of water. If you do not reduce incoming gas pres-
sure, heater regulator damage could occur. Install
the external regulator with the vent pointing down
as shown in Figure 14. Pointing the vent down
protects it from freezing rain or sleet.
Figure 14 - External Regulator With Vent
Pointing Down
External
Regulator
Propane/LP
Supply Tank
Vent
Pointing
Down

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12
Tee Pipe Cap
Joint Nipple
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 Diameters
VN18A, VN18TA, VP16A, VP16TA and
VP16ITA - 3/8" or greater
VN30A, VN30TA, VP26A, VP26TA and
VP22ITA - 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 15).
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.
Install sediment trap in supply line as shown in
Figure 15. 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.
INSTALLATION
Continued
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 Accessories, page 33.
Figure 15 - Gas Connection
Pressure
Regulator
Test Gauge Connection*
Heater
Cabinet
Sediment Trap
Equipment
Shutoff
Valve *
3"
Min.
Natural Gas
From Gas
Meter (7" W.C.
to 10.5" W.C.
Pressure)
Propane/LP
From External
Regulator
(11" W.C. to 14"
W.C. Pressure)
Regulator
Bracket
Ground
Joint
Union
3/8" NPT
Pipe
Nipple
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 detec-
tion fluid to all joints. Bubbles
forming 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 11.

www.desatech.com 13113052-01D
INSTALLATION
Continued
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 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.
Test Pressures Equal To or Less Than 1/2
PSIG (3.5 kPa)
1. Close equipment shutoff valve (see Figure 16).
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 17) or propane/LP supply tank for
propane/LP gas, to equipment shutoff valve
(see Figure 18). 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 16).
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 17 or 18).
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 14
). Check all other internal joints for leaks.
7. Turn off heater (see To Turn Off Gas to Ap-
pliance, page 15 or 17 depending on your
model).
8. Replace front panel.
Figure 18 - Checking Gas Joints for
Propane/LP Gas
Figure 16 - Equipment Shutoff Valve
Equipment
Shutoff
Valve
Propane/LP
Supply Tank
Thermostat Gas Valve
Open
Closed
Equipment
Shutoff Valve
Figure 17 - Checking Gas Joints for
Natural Gas
Equipment
Shutoff Valve
Gas
Meter
Thermostat Gas Valve

www.desatech.com 113052-01D
14
OPERATING HEATER
NON-THERMOSTAT 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
1. STOP! Read the safety information above.
2. Make sure equipment shutoff valve is fully
open.
3. Turn control 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. Turn control knob to PILOT/IGN and
press in.
Note: You may be running this heater for
the first time after hooking up to gas supply.
If so, you may need to press in control knob
for 30 seconds or more. This will allow air
to bleed from the gas system.
• If control knob does not pop up when
released, contact a qualified service
person or gas supplier for repairs.
6. With control knob pressed in, push down
and release ignitor button. This will light
pilot. The pilot is attached to the front of
burner. If needed, keep pressing ignitor
button until pilot lights.
If pilot does not light
• turn control knob clockwise to
the OFF position
• repeat steps 5 and 6
If pilot does not stay lit after several tries
• refer to Troubleshooting, page 20
• contact a qualified service person or gas
supplier for repairs
Until repairs are made, light pilot with
match. To light pilot with match, see
Manual Lighting Procedure, page 15.
7. Keep control knob pressed in for 30 seconds
after lighting pilot. After 30 seconds, release
control knob. Note: If pilot goes out, repeat
steps 3 through 7.
OFF
Ignitor Button Control Knob
Figure 19 - Control Knob In The OFF
Position for Non-Thermostat Models
Figure 20 - Pilot
Ignitor Electrode
Pilot
Burner
Thermocouple

www.desatech.com 15113052-01D
TO SELECT
HEATING LEVEL
WARNING: When running
heater, set control knob at LOW,
MEDIUM or HIGH locked posi-
tions. Never set control knob
between locked positions. Poor
combustion and higher levels of
carbon monoxide may result.
CAUTION: Do not try to ad-
just heating levels by using the
equipment shutoff valve.
Slightly press in control knob and turn coun-
terclockwise to the LOW, MED or HI
positions (see Figure 21).
IMPORTANT: Release downward pressure
while turning control knob. Control knob will
lock at the desired position.
OPERATING HEATER
Continued
LOW
HI
OFF
MED
Control VN18A VN30A
Knob VP16A VP26A
Figure 21 - Burner Patterns for Non-
Thermostat Models
TO TURN OFF GAS
TO APPLIANCE
Shutting Off Heater
1. Turn control knob clockwise to the
OFF position.
2. Turn off all electric power to the appliance
if service is to be performed.
Shutting Off Burner Only (pilot stays lit)
Turn control knob clockwise to the
PILOT position.
MANUAL LIGHTING
PROCEDURE
1. Remove front panel (see Figure 7, page 8).
2. Follow steps 1 through 5 under Lighting
Instructions, page 14.
3. With control knob pressed in, strike match.
Hold match to pilot until pilot lights.
4. Keep control knob pressed in for 30 seconds
after lighting pilot. After 30 seconds, release
control knob. Now follow step 8, under
Lighting Instructions, page 14.
5. Replace front panel.
THERMOSTAT 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.

www.desatech.com 113052-01D
16
O
F
F
P
I
L
O
T
LIGHTING
INSTRUCTIONS
1. STOP! Read the safety information, page
15, column 2.
2. Make sure equipment shutoff valve is fully
open.
3. Turn thermostat control knob clockwise
to the OFF position (see Figure 22
or 23 for your model).
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, page 15, column 2. If you donʼt
smell gas, go to the next step.
5. Turn thermostat control knob counter-
clockwise to the PILOT position.
Press in thermostat control knob for 5 sec-
onds (see Figure 22 or 23 for your model).
Note: You may be running this heater for
the first time after hooking up to gas supply.
If so, you may need to press in thermostat
control knob for 30 seconds or more. This
will allow air to bleed from the gas system.
• If thermostat control knob does not pop
up when released, contact a qualified ser-
vice person or gas supplier for repairs.
6. Keep thermostat control knob pressed in while
pushing down and releasing the ignitor button.
This will light pilot. If necessary, continue to
press ignitor button until pilot lights.
If pilot does not light
• turn thermostat control knob clockwise
to the OFF position
• repeat steps 5 and 6
If pilot does not stay lit after several tries
• refer to Troubleshooting, page 20
• contact a qualified service person or gas
supplier
Until repairs are made, light pilot with
match. To light pilot with match, see
Manual Lighting Procedure, page 17.
7. Keep thermostat control knob pressed in
for 30 seconds after lighting pilot. After 30
seconds, release control knob.
Note: If pilot goes out, repeat steps 3
through 7. This heater has a safety interlock
system. Wait one minute before lighting
pilot again.
OPERATING HEATER
Continued
8. Turn thermostat control knob counter-
clockwise to the desired heating
level. For models, VP16TA, VN18TA,
VP26TA and VN30TA, the main burner
should light. Set control knob to any heat
level between 1 and 5 (see Figure 25). For
infrastat models, the plaque directly above
the pilot should light.
CAUTION: Do not try to ad-
just heating levels by using the
equipment shutoff valve.
Figure 22 - Control Knob In The OFF
Position, Models VP16TA, VN18TA,
VP26TA, & VN30TA
Control Knob
Ignitor Button
Figure 24 - Pilot
Figure 25 - Burner Patterns
Control
Knob
VP16TA
VN18TA
VP26TA
VN30TA
Ignitor Electrode
Pilot Burner
Thermocouple
Figure 23 - Thermostat Control Knob In The
OFF Position, Models VP16ITA & VP22ITA
1
2
3
4
O
F
F
P
I
L
O
T
Thermostat
Control Knob
Plaque Control
Knob
Ignitor
Button

www.desatech.com 17113052-01D
TO SELECT
HEATING LEVEL
INFRASTAT MODELS VP16ITA AND
VP22ITA ONLY
WARNING: When running
heater, set control knob at the
1, 2, 3 or 4 locked positions.
Never set control knob between
locked positions. Poor combus-
tion and higher levels of carbon
monoxide may result.
CAUTION: Do not try to ad-
just heating levels by using the
equipment shutoff valve.
1. Slightly press in plaque control knob on
right side of heater and turn counterclock-
wise to the desired position.
IMPORTANT: Release downward pressure
while turning control knob. Control knob
will lock at the desired position.
2. For standard models (T), turn thermostat
control knob on left side of heater to any set-
ting between LO and HI. For infrastat models
(ITA), set thermostat control knob at the 1, 2,
3 or 4, locked positions. Note: When burn-
ers cycle on, (from LO to HI or one locked
positions to another) a “click” will be heard.
When the burners light, a “whoosh” noise
will be heard.
OPERATING HEATER
Continued
TO TURN OFF GAS
TO APPLIANCE
Shutting Off Heater
1. Turn thermostat control knob clockwise
to the OFF position.
2. Turn off all electric power to the appliance
if service is to be performed.
Shutting Off Burner Only (pilot stays lit)
Turn thermostat control knob clockwise
to the PILOT position.
THERMOSTAT
OPERATION
The thermostatic control used on these models
differs from standard thermostats. Standard
thermostats simply turn on and off the burner.
The thermostat used on this heater senses the
room temperature. At times the room may ex-
ceed 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. For standard models (T), the control knob
can be set to any heating level between 1 and 5.
All plaques will turn off and on. For infrastat
models (ITA), the control knob can be set at
the 1, 2, 3 or 4 locked positions for the desired
comfort level. The number of plaques selected
will turn off and on.
Note: The thermostat sensing bulb measures
the temperature of air near the heater cabinet.
This may not always agree with room tem-
perature (depending on housing construction,
installation location, room size, open air tem-
peratures, etc.) Frequent use of your heater will
let you determine your own comfort levels.
MANUAL LIGHTING
PROCEDURE
1. Remove front panel (see Figure 7, page 8).
2. Follow steps 1 through 5 under Lighting
Instructions, page 16.
3. With thermostat control knob pressed in,
strike match. Hold match to pilot until pilot
lights.
4. Keep thermostat control knob pressed in
for 30 seconds after lighting pilot. After 30
seconds, release control knob. Follow step
8 under Lighting Instructions, page 16.
5. Replace front panel.
Plaque
Control Knob VP16ITA VP22ITA
Figure 26 - Burner Patterns, Models
VP16ITA and VP22ITA
1
2
3
4
1
2
3
4
1
2
3
4
1
2
3
4

www.desatech.com 113052-01D
18
Thermocouple Pilot Burner
Pilot Burner
Thermocouple
Blue Flame
Yellow Flame
Figure 27 - Correct Pilot Flame Pattern
Figure 28 - Incorrect Pilot Flame Pattern
Figure 29 - Correct Burner Flame Pattern
INSPECTING HEATER
Check pilot flame pattern and burner flame pat-
tern often.
PILOT FLAME PATTERN
Figure 27 shows a correct pilot flame pattern.
Figure 28 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 28
• turn heater off (see To Turn Off Gas to Ap-
pliance, page 15 or 17, depending on your
model)
• see Troubleshooting, page 20
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.
Figure 30 - Incorrect Burner Flame
Pattern
BURNER FLAME PATTERN
Figure 29 shows a correct burner flame pattern. Fig-
ure 30 shows an incorrect burner flame pattern.
If burner flame pattern is incorrect, as shown in
Figure 30
• turn heater off (see To Turn Off Gas to Ap-
pliance, page 15 or 17, depending on your
model)
• see Troubleshooting, page 20

www.desatech.com 19113052-01D
CLEANING AND
MAINTENANCE
WARNING: Turn off heater
and let cool before cleaning.
CAUTION: You must keep
control areas, burner and circu-
lating 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 clean-
ing 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. 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 com-
pressed air in a can, please follow the directions on
the can. If you donʼt 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 31). 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.
Figure 31 - Pilot Air Inlet
Pilot Assembly
Pilot Air Inlet

www.desatech.com 113052-01D
20
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
installed correctly (electronic
ignition models only)
1. Gas supply turned off or equip-
ment shutoff valve closed
2. Control knob not fully pressed
in while pressing ignitor but-
ton (non-thermostat models
only)
Thermostat control knob not
fully pressed in while press-
ing ignitor button (thermostat
models only)
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
7. Thermostat control knob is not
in pilot position (thermostat
models only)
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
battery is installed correctly
1. Turn on gas supply or open
equipment shutoff valve
2. Turn to PILOT/IGN position.
Fully press in control knob
while pressing ignitor button
(non-thermostat models only)
Fully press in thermostat
control knob while pressing
ignitor button (thermostat
models only)
3. Continue holding down con-
trol knob. Repeat igniting op-
eration until air is removed
4. Contact local propane/LP gas
company
5. Clean ODS/pilot (see Cleaning
and Maintenance, page 19) or
replace ODS/pilot assembly
6. Replace gas regulator
7. Turn thermostat control knob
to pilot position
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