Osburn 3500-I User manual

Installation and
Operation Manual
2.5 g/h
<
≤
EPA
CONTACT LOCAL BUILDING OR FIRE OFFICIALS ABOUT RESTRICTIONS AND INSTALLATION INSPECTION REQUIREMENTS IN
THE AREA.
READ THIS ENTIRE MANUAL BEFORE INSTALLATION AND USE OF THIS WOOD INSERT. FAILURE TO FOLLOW THESE
INSTRUCTIONS COULD RESULT IN PROPERTY DAMAGE, BODILY INJURY OR EVEN DEATH.
US Environmental Protection
Agency phase II certified
wood insert compliant with
2020 cord wood standard.
Safety tested according to
ULC S628, UL 1482 and
UL 737 by an accredited
laboratory.
OSBURN 3500-I
(OB03510 Model)
ENGLISH
READ AND KEEP THIS MANUAL FOR REFERENCE
Printed in Canada 46180A
2020-07-15

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As one of North America’s
largest and most respected
wood stove and fireplace
manufacturers, Stove Builder
International takes pride in the
quality and performance of all
its products.
The following pages provide
general advice on wood
heating, detailed instructions
for safe and effective
installation, and guidance
on how to get the best
performance from this insert.
It is highly recommended
that this wood burning hearth
product be installed and
serviced by professionals who
are certified by NFI (National
Fireplace Institute®) or CSIA
(Chimney Safety Institude
of America) in the United
States or in Canada by WETT
(Wood Energy Technology
Transfer) or in Quebec
by APC (Association des
Professionnels du Chauffage).
Contact local building or fire
officials about restrictions
and installation inspection
requirements in the area.
A building permit might be
required for the installation of
this insert and the chimney
that it is connected to. It
is also recommended to
inform your home insurance
company.
Please read this entire manual
before installing and using this
insert.
A primary alternative heat
source should be available in
the home. This heating unit
may serve as a supplementary
heat source. The manufacturer
cannot be responsible for
additional heating costs
associated with the use of an
alternative heat source.
THANK YOU FOR CHOOSING
THIS WOOD INSERT.
If this insert is not
installed properly,
combustible materials
near it may overheat
and catch fire.
To reduce the
risk of fire, follow
the installation
instructions in this
manual.
ONLINE WARRANTY REGISTRATION
If the unit requires repairs during the warranty period, proof of purchase must be provided. The
purchase invoice must be kept. The date indicated on it establishes the warranty period. If it
cannot be provided, the warranty period will be determined by the date of manufacture of the
product. It is also highly recommended to register the warranty online at
https://www.osburn-mfg.com/en/warranty/warranty-registration/
Registering the warranty will help to quickly nd the information needed on the unit.

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TABLE OF CONTENTS
PART A - OPERATION AND MAINTENANCE .............................................................................. 7
1. Safety Information................................................................................................................... 7
2. General Information ................................................................................................................ 8
2.1 Performances................................................................................................................. 8
2.2 Specifications................................................................................................................. 9
2.3 Dimensions ..................................................................................................................10
2.4 Materials .......................................................................................................................12
2.5 Zone Heating.................................................................................................................12
2.6 Emissions and Efficiency ................................................................................................13
3. Fuel ........................................................................................................................................ 13
3.1 Tree Species .................................................................................................................14
3.2 Log Length....................................................................................................................14
3.3 Piece Size .....................................................................................................................14
3.4 Compressed Wood Logs................................................................................................14
3.5 Drying Time...................................................................................................................15
4. Operating the Insert .............................................................................................................. 16
4.1 Blower ..........................................................................................................................17
4.2 Fire Screen....................................................................................................................17
5. Burning Wood Efficiently ...................................................................................................... 18
5.1 First Use .......................................................................................................................18
5.2 Lighting Fires.................................................................................................................18
5.3 Combustion Cycles........................................................................................................19
5.4 Rekindling a Fire............................................................................................................20
5.5 Removing Ashes............................................................................................................20
5.6 Air Intake Control ..........................................................................................................21
5.7 Fire Types .....................................................................................................................21
6. Maintenance.......................................................................................................................... 23
6.1 Insert ............................................................................................................................23
6.2 Glass Door....................................................................................................................23
6.3 Door .............................................................................................................................25
6.4 Exhaust System.............................................................................................................27
PART B - INSTALLATION............................................................................................................ 29
7. Masonry Fireplace Requirements ........................................................................................ 29
7.1 Fireplace and Chimney Condition....................................................................................29
7.2 Chimney Caps...............................................................................................................29
7.3 Adjacent Combustibles ..................................................................................................29
7.4 Opening Size.................................................................................................................29
7.5 Masonry Fireplace Throat Damper ..................................................................................29

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8. Safety Information and Standards ....................................................................................... 30
8.1 Regulations Covering Insert Installation ...........................................................................30
8.2 Certification Label..........................................................................................................30
9. Clearances to Combustible Material.................................................................................... 31
9.1 Installation of a Combustible Mantel Shelf .......................................................................31
9.2 Floor Protection.............................................................................................................31
9.3 Minimum Masonry Opening and Clearances to Combustibles ...........................................34
10.The Venting System .............................................................................................................. 35
10.1 General ........................................................................................................................35
10.2 Block-off Plate...............................................................................................................35
10.3 Suitable Chimneys .........................................................................................................35
10.4 Chimney Liner Installation...............................................................................................36
10.5 Liner Connection ...........................................................................................................36
10.6 Minimum Chimney Height...............................................................................................38
10.7 Chimney Location..........................................................................................................38
10.8 Supply of Combustion Air...............................................................................................39
Appendix 1: Blower and Ash Lip Installation ........................................................................... 40
Appendix 2: Door Overlay Installation...................................................................................... 41
Appendix 3: Fresh Air Intake Kit Installation ............................................................................ 42
Appendix 4: Faceplate And Trims Installation.......................................................................... 43
Appendix 5: Optional Fire Screen Installation.......................................................................... 47
Appendix 6: Air Tubes and Baffle Installation .......................................................................... 48
Appendix 7: Removal Instructions............................................................................................ 50
Appendix 8: Exploded Diagram and Parts List........................................................................ 51
Osburn Limited Lifetime Warranty ............................................................................................ 54
Dealer:
Installer:
Phone Number:
Serial Number:

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CERTIFICATION PLATE

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PART A - OPERATION AND MAINTENANCE
1. Safety Information
• This insert has been tested for use with an open door in conjunction with a fire screen, sold
separately. The door may be opened, or fire screen removed only during lighting procedures or
reloading. Always close the door or put back on the fire screen after ignition. Do not leave the insert
unattended when the door is opened with or without a fire screen.
• WARNING : OPERATE ONLY WITH THE DOOR FULLY CLOSED OR FULLY OPEN WITH THE
FIRE SCREEN IN PLACE. IF THE DOOR IS LEFT PARTLY OPEN, GAS AND FLAME MAY BE
DRAWN OUT OF THE OPENING, CREATING RISKS FROM BOTH FIRE AND SMOKE.
• HOT WHILE IN OPERATION, KEEP CHILDREN, CLOTHING AND FURNITURE AWAY.
CONTACT MAY CAUSE SKIN BURNS. GLOVES MAY BE NEEDED FOR INSERT OPERATION.
• Using an insert with cracked or broken components, such as glass, firebricks or baffle may produce
an unsafe condition and may damage the insert.
• Open the air control fully before opening the loading door.
• NEVER USE GASOLINE, LANTERN FUEL (NAPHTHA), FUEL OIL, MOTOR OIL, KEROSENE,
CHARCOAL LIGHTER FLUID, OR SIMILAR LIQUIDS OR AEROSOLS TO START A FIRE IN
THIS INSERT. KEEP ALL SUCH LIQUIDS OR AEROSOLS WELL AWAY FROM THE INSERT
WHILE IT IS IN USE.
• Do not store fuel within heater minimum installation clearances.
• Burn only seasoned natural firewood.
• This wood heater needs periodic inspection and repair for proper operation. It is against federal
regulations to operate this wood heater in a manner inconsistent with operating instructions in this
manual.
• This appliance should always be maintained and operated in accordance with these instructions.
• Do not elevate the fire by means of grates, andirons or other means.
• A smoke detector, a carbon monoxide detector and a fire extinguisher should be installed in the
house. The location of the fire extinguisher should be known by all family members.
• Do not use makeshift materials or make any compromises when installing this insert.
This product can expose you to chemicals including carbon monoxide, which is
known to the State of California to cause cancer, birth defects or other reproductive
harm. For more information go to www.P65warnings.ca.gov/

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2. General Information
2.1 Performances
Values are as measured per test method, except for the recommended heating area, firebox volume,
maximum burn time and maximum heat output.
Models Osburn 3500-I (OB03510)
Fuel Type Dry Cordwood
Combustion technology Non-catalytic
Recommended heating area (sq. ft..)1 1,000 to 2,700 ft2(93 to 251 m2)
Nominal firebox volume 3.5 ft3(0.099 m3)
EPA loading volume 2.84 ft3(0.056 m3)
Maximum burn time110 hours
Maximum heat output (dry cordwood)2 110,000 BTU/h (32.2 kW)
Overall heat output rate (min. to max.)2 3 18,100 BTU/h to 49,500 BTU/h
(5.3 kW to 14.5 kW)
Average overall efficiency3
Dry cordwood 71 % (HHV)4 76 % (LHV)5
Optimum efficiency6 77 %
Average particulate emissions rate7 1.32 g/h (EPA / CSA B415.1-10)8
Average CO9 92 g/h
1Recommended heating area and maximum burn time may vary subject to location in home, chimney draft,heat loss factors, climate, fuel type
and other variables. The recommended heated area for a given appliance is dened by the manufacturer as its capacity to maintain a minimum
acceptable temperature in the designated area in case of a power failure.
2The maximum heat output (dry cordwood) is based on a loading density varying between 15 lb/ft3and 20 lb/ft3. Other performances are based on
a fuel load prescribed by the standard. The specied loading density varies between 7 lb/ft³ and 12 lb/ft3. The moisture content is between 19%
and 25%.
3As measured per CSA B415.1-10 stack loss method.
4Higher Heating Value of the fuel.
5Lower Heating Value of the fuel.
6Optimum overall efciency at a specic burn rate (LHV).
7This appliance is ofcially tested and certied by an independent agency
8Tested and certied in compliance with CFR 40 part 60, subpart AAA, section 60.534(a)(1(ii) and ASTM E3053-17 based on the ATM send by EPA
on October 12th, 2017.
9Carbon monoxide.

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2.2 Specifications
Maximum log length10 22 in (560 mm) east-west
Flue outlet diameter 6 in (150 mm)
Recommended connector pipe diameter 6 in (150 mm)
Type of chimney ULC S635, CAN/ULC-S640, UL 1777
Baffle material C-Cast
Approved for alcove installation Not applicable
Approved for mobile home installation11 No
Type of door Simple, glass with cast iron frame
Type of glass Ceramic glass
Blower Included (Up to 144 CFM)
Particulate emission standard EPA / CSA B415.1-1012
USA Standard (Safety) UL 1482, UL 737
Canada Standard (Safety) ULC-S628
10 North-south: ends of the logs visible, East-west: sides of the logs visible.
11 Mobile homes (Canada) or manufactured homes (USA): The US Department of Housing and Urban Development describes “manufactured homes”
better known as “mobile homes” as follows; buildings built on xed wheels and those transported on temporary wheels/axles and set on a permanent
foundation. In Canada, a mobile home is a dwelling for which the manufacture and assembly of each component is completed or substantially
completed prior to being moved to a site for installation on a foundation and connection to service facilities and which conforms to the CAN/CSA-
Z240 MH standard.
12 Tested and certied in compliance with CFR 40 part 60, subpart AAA, section 60.534(a)(1(ii) and ASTM E3053-17 based on the ATM send by EPA
on October 12th, 2017.

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2.3 Dimensions
27 3/4"
706mm
14 3/8"
366mm
30 3/8"
773mm 28 3/4"
731mm
ø6"
153mm
7 1/8"
182mm
18 1/4"
464mm
4 7/8"
122mm
MIN
Top View Side View - Minimum Insert Projection
27 5/8"
703mm
11 3/4"
298mm
19"
482mm
21 1/4"
540mm
1 7/8"
48mm
MAX
24 1/8"
614mm
24 1/2"
623mm 24 7/8"
631mm
9 1/8"
232mm
23 1/8"
586mm24 1/8"
613mm
29"
735mm
23 1/4"
591mm
Front View Side View - Maximum Insert Projection

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19"
483mm
10 5/8"
269mm
Door Opening
22 7/8"
581mm
3/16"
5mm
3/8"
10mm
20 1/8"
510mm
12 7/8"
326mm
Front View - Combustion Chamber Side View - Combustion Chamber

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2.4 Materials
The SBI team is committed to protecting the environment, so they do everything they can to use
only materials in their products that will have no lasting negative impact on the environment.
The body of this insert, which is most of its weight, is carbon steel. Should it ever become
necessary many years in the future, almost the entire insert can be recycled into new products,
thus eliminating the need to mine new materials.
The paint coating on the insert is very thin. Its VOC content (Volatile Organic Compounds) is
very low. VOCs can be responsible for smog, so all the paint used during the manufacturing
process meets the latest air quality requirements regarding VOC reduction or elimination.
The air tubes are stainless steel, which can also be recycled.
The C-Cast baffle is made of aluminosilicate fibre material that is compressed with a binder
to form a rigid board. C-Cast can withstand temperatures above 2,000 °F. It is not considered
hazardous waste. Disposal at an ecocentre is recommended.
The firebricks are mainly composed of silicon dioxide, also known as silica, a product processed
from a mined mineral. It is most commonly found in nature in the form of sand and clay. Disposal
at an ecocentre is recommended.
The door and glass gaskets are fibreglass which is spun from melted sand. Black gaskets have
been dipped into a solvent-free solution. Disposal at an ecocentre is recommended.
The door glass is a 5/32" (4 mm) thick ceramic material that contains no toxic chemicals. It is
made of natural raw materials such as sand and quartz that are combined in such a way to form
a high temperature glass. Ceramic glass cannot be recycled in the same way as normal glass,
so it should not be disposed of with the regular household products. Disposal at an ecocentre
is recommended.
2.5 Zone Heating
This insert is a space heater, which means it is intended to heat the area it is installed in, as well
as spaces that connect to that area, although to a lower temperature. This is called zone heating
and it is an increasingly popular way to heat homes or spaces within homes.
Zone heating can be used to supplement another heating system by heating a particular space
within a home, such as a basement, a family room or an addition that lacks another heat source.
Houses of moderate size and relatively new construction can be heated with a properly sized
and located wood insert. Whole house zone heating works best when the insert is in the part of
the house where the family spends most of its time. This is normally the main living area where
the kitchen, dining and living rooms are located.
Locating the insert in this area will give the maximum benefit of the heat it produces and will
achieve the highest possible heating efficiency and comfort. The space where the most time is
spent will be warmest, while bedrooms and basement (if there is one) will stay cooler. In this
way, less wood is burned than with other forms of heating.

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Although the insert may be able to heat the main living areas of the house to an adequate
temperature, it is strongly recommended to also have a conventional oil, gas or electric heating
system to provide backup heating.
The success of zone heating will depend on several factors, including the correct sizing and
location of the insert, the size, layout and age of the home and the climate zone. Three-season
vacation homes can usually be heated with smaller inserts than houses that are heated all winter.
2.6 Emissions and Efficiency
The low smoke emissions produced by the special features inside this insert firebox means
that the household will release up to 90% less smoke into the outside environment than if an
older conventional insert was used. But there is more to the emission control technologies than
protecting the environment.
The smoke released from wood when it is heated contains about half of the energy content of
the fuel. By burning the wood completely, this insert releases all the heat energy from the wood
instead of wasting it as smoke up the chimney. Also, the features inside the firebox allow control
of the air supply meaning controlling the heat output, while maintaining clean and efficient
flaming combustion, which boosts the efficient delivery of heat to the home.
The emission control and advanced combustion features of this insert can only work properly
if the fuel used is in the correct moisture content range of 15% to 20%. Refer to the following
section for suggestions on preparing fuelwood and judging its moisture.
3. Fuel
Good firewood has been cut to the correct length for the insert, split to a range of sizes and
stacked in an open area until its moisture content is down to 15% to 20%.
DO NOT BURN:
• Garbage;
• Lawn clippings or yard waste;
• Materials containing rubber, including tires;
• Materials containing plastic;
• Waste petroleum products, paints or paint
thinners, or asphalt products;
• Materials containing asbestos;
• Construction or demolition debris;
• Railroad ties or pressure-treated wood;
• Manure or animal remains;
• Salt water driftwood or other previously salt
water saturated materials;
• Unseasoned wood; or
• Paper products, cardboard, plywood, or
particleboard. the prohibition against burning
these materials does not prohibit the use of fire
starters made from paper, cardboard, saw dust,
wax and similar substances for the purpose of
starting a fire in an affected wood heater.
Burning these materials may result in release of toxic fumes or render the heater ineffective and
cause smoke.

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3.1 Tree Species
The tree species the firewood is produced from is less important than its moisture content. The
main difference in firewood from various tree species is the density of the wood. Hardwoods are
denser than softwoods.
Homeowners with access to both hardwood and softwood use both types for different purposes.
Softer woods make good fuel for mild weather in spring and fall because they light quickly and
produce less heat. Softwoods are not as dense as hardwoods so a given volume of wood
contains less energy. Using softwoods avoids overheating the house, which can be a common
problem with wood heating in moderate weather. Harder woods are best for colder winter
weather when more heat and longer burn cycles are desirable.
Note that hardwood trees like oak, maple, ash and beech are slower growing and longer lived
than softer woods like poplar and birch. That makes hardwood trees more valuable. The advice
that only hardwoods are good to burn is outdated. Old, leaky cast iron inserts wouldn’t hold a
fire overnight unless they were fed large pieces of hardwood. That is no longer true.
3.2 Log Length
Logs should be cut at least 1" (25 mm) shorter than the firebox so they fit in
easily. Pieces that are even slightly too long makes loading the insert very
difficult. The most common standard length of firewood is 16" (400 mm).
3.3 Piece Size
Firewood dries more quickly when it is split. Large unsplit rounds can take years to dry enough
to burn. Even when dried, unsplit logs are difficult to ignite because they don’t have the sharp
edges where the flames first catch.
Wood should be split to a range of sizes, from about 3" to 6" (75 mm to 150 mm) in cross
section. Having a range of sizes makes starting and rekindling fires much easier.
3.4 Compressed Wood Logs
Compressed wood logs made of 100% compressed sawdust can be
burned with caution in the number of these logs burned at once. Do
not burn compressed logs made of wax impregnated sawdust or logs
with any chemical additives. Follow the manufacturer’s instructions
and warnings.

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3.5 Drying Time
Firewood that is not dry enough to burn is the cause of most complaints about wood inserts.
Continually burning green or unseasoned wood produces more creosote and involves lack of
heat and dirty glass door.
Firewood with a moisture content between 15% and 20% will allow the insert to produce its
highest possible efficiency.
Here are some facts to consider in estimating drying time:
− Firewood bought from a dealer is rarely
dry enough to burn, so it is advisable
to buy the wood in spring and dry it
yourself;
− Drying happens faster in dry weather
than in a damp climate;
− Drying happens faster in warm summer
weather than in winter weather;
− Small pieces dry more quickly than
large pieces;
− Split pieces dry more quickly than
unsplit rounds;
− Softwoods like pine, spruce, poplar, and aspen take less time to dry than hardwoods. they can be
dry enough to burn after being stacked to air dry only for the summer months;
− Hardwoods like oak, maple and ash can take one, or even two years to dry fully, especially if the
pieces are big;
− Firewood dries more quickly when stacked outside in a location exposed to sun and wind; it takes
much longer to dry when stacked in a wood shed.
Use these guidelines to find out if the firewood is dry enough to burn:
− Cracks form at the ends of logs as they dry;
− The wood turns from white or cream colored to grey or yellow;
− Two pieces of wood struck together sounds hollow;
− Dry wood is much lighter in weight than wet wood,
− The face of a fresh cut feels warm and dry;
− The moisture content read by a moisture meter is between
15% to 20%.

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4. Operating the Insert
This wood heater has a manufacturer-set minimum low burn rate that must not be
altered. It is against federal regulations to alter this setting or otherwise operate this
wood heater in a manner inconsistent with operating instructions in this manual.
Before using the insert, the following steps should be completed :
• Empty the combustion chamber and install the air control handle (A) with the set screw (B) as
shown below:
A
B
Empty the combustion chamber Installing the air control wood handle
• Install the combustion chamber side bricks as shown below.
• Install the ash lip and the blower (see «Appendix 1: Blower and Ash Lip Installation»);
• Install the door overlay (see «Appendix 2: Door Overlay Installation»);
• Install the faceplate (See «Appendix 4: Faceplate And Trims Installation»).
The following step is optional :
• Install the fresh air intake (See «Appendix 3: Fresh Air Intake Kit Installation»).

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4.1 Blower
A blower is already installed on this insert. It is located
underneath the ash lip, in front of the insert. Its function
is to increase airflow through the heat exchanger and
improve hot air circulation in the room. When used
regularly, the blower can provide a small increase in
efficiency, up to 2%. However, the use of a blower
should not be used as a way to gain more output from
an insert that is undersized for the space it is intended
to heat.
Blower location
The blower has a rheostat that can be adjusted in three different
positions; either from high (HI) to low (LO) or closed (OFF).
Allow the insert to reach operating temperature (approximately
one hour) before turning on the blower, since increased airflow
from the blower will remove heat and affect the start up
combustion efficiency.
The blower is also equipped with a heat sensor. When the
blower is ON, it will start automatically when the insert is hot
enough and it will stop when the insert has cooled down.
Therefore, the blower speed control can be left at the desired
setting.
OFF
HI
LO
Blower rheostat
4.2 Fire Screen
This insert has been tested for use with an open door in conjunction with a fire screen, sold
separately. The fire screen must be properly secured on the insert to avoid any risk of sparks
damaging the flooring. When the fire screen is in use, do not leave the insert unattended to
respond promptly in the event of smoke spillage into the room. Potential causes of smoke
spillage are described in Section «10. The Venting System» of this manual. See «Appendix 5:
Optional Fire Screen Installation» for installation instructions.
OPERATING THE INSERT WITH A FIRE SCREEN INCREASES POSSIBILITIES OF
GENERATING CARBON MONOXIDE. CARBON MONOXIDE IS AN ODOURLESS GAS THAT
IS HIGHLY TOXIC WHICH CAN CAUSE DEATH AT HIGH CONCENTRATION IN AIR.
Ensure the blower cord is not in contact
with any surface of the insert to prevent
electrical shock or fire damage. Do not
run cord beneath the insert.

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5. Burning Wood Efficiently
5.1 First Use
Two things happen when burning the first few fires; the paint cures and the internal components are
conditioned. As the paint cures, some of the chemicals vaporize. The vapors are not poisonous,
but they smell bad. Fresh paint fumes can also trigger false alarms in smoke detectors.
When lighting the heater for the first few times, it may be wise to open doors and windows to
ventilate the house.
Burn two or three small fires to begin the curing and conditioning process. Then build bigger
and hotter fires until there is no longer paint smell from the insert. As hotter and hotter fires are
burned, more of the painted surfaces reach the curing temperature of the paint. The smell of
curing paint does not disappear until one or two very hot fires have been burned.
5.2 Lighting Fires
Each person heating with wood develops its own favorite way to light fires. Regardless of the
method chosen, the goal should be to have a hot fire burning, quickly. A fire that ignites fast
produces less smoke and deposits less creosote in the chimney.
Here are three popular and effective ways to ignite wood fires.
5.2.1 Conventional Method
The conventional method to build a wood fire is to crumple 5
to 10 sheets of newspaper and place them in the firebox and
hold them in place with ten pieces of kindling wood. The kindling
should be placed on and behind the newspaper.
Then add two or three small pieces of firewood. Open the air
intake control completely and ignite the newspaper. Leave the
door slightly ajar.Once the fire has ignited, the door can be closed
with the air control still fully open. When the kindling is almost
completely burned, standard firewood pieces can be added.
Do not leave the insert unattended when the door is slightly open. Always close and latch the
door after the fire ignites.
5.2.2 The Top Down Method
This method is the opposite of the conventional method and only works properly if well-seasoned
wood is used.
Place three or four small, split, dry logs in the firebox. Arrange the kindling wood on the logs in
two layers at right angles and place a dozen finely split kindling on the second row.
It is possible to use ragged paper but it may not hold in place since it tends to roll while it is
burning. The best is to wrap a sheet on itself, grab the ends of the roll and make a knot.
Never use gasoline, gasoline-type lantern fuel (naphtha), fuel oil, motor oil,
kerosene, charcoal lighter fluid, or similar liquids or aerosols to start or
‘freshen up’ a fire in this wood insert. Keep all such liquids well away from
the insert while it is in use.

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Use four or five sheets of paper tied together and put them on top and around the kindling. Open
the air intake control completely, ignite the paper and close the door.
The down fire method has two advantages over the traditional method: first, the fire does not
collapse on itself, and it is not necessary to add wood gradually since the combustion chamber
is full before the fire is lit.
5.2.3 Two Parallel Logs Method
Two spit logs are placed in the firebox with a few sheets of twisted newspapers in between the
logs. Fine kindling is added across the two logs and some larger kindling across those, log cabin
style. Newspaper is lit.
5.2.4 Using Fire Starters
Commercial fire starters can be used instead of a newspaper. Some of these starters are made
of sawdust and wax and others are made of specialized flammable solid chemicals. Always
follow the package directions when using.
Gel starters can also be used, but only to light a fire, in a cold combustion chamber without hot
embers inside.
5.3 Combustion Cycles
Wood heating with a space heater is very different than other forms of heating. There will be
temperature variations in different parts of the house and there will be temperature variations
throughout day and night. This is normal, and for experienced wood burners these are advantages
of zone heating wood burning.
Wood heaters don’t have a steady heat output. It is normal for the temperature to rise after
a new load of wood is ignited and for its temperature to gradually decrease throughout the
burning cycle. This increasing and decreasing temperature can be matched with the household
routines. For example, the temperature in the area can be cooler when the household is active,
and it can be warmer when it is inactive.
Wood burns best in cycles. A cycle starts when a new load of wood is ignited by hot coals and
ends when that load has been consumed down to a bed of charcoal about the same size as it
was when the wood was loaded.
Trying to produce a steady heat output by placing a single log on the fire at regular intervals
is not recommended. Always place at least three, and preferably more pieces on the fire at a
time so that the heat radiated from one piece helps to ignite the pieces next to it. Each load of
wood should provide several hours of heating. The size of each load may vary depending on the
amount of heat required.
Burning in cycles means the loading door does not need to be opened while the wood is flaming.
This is an advantage since it is preventing smoke leaking from the heater when the door is
opened as a full fire is burning. This is especially true if the chimney is on the outside wall of the
house.
If the door must be opened while the fire is flaming, fully open air control for a few
minutes then open the door slowly.

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5.4 Rekindling a Fire
When the temperature of the room is lower and all that remains is embers, it is time to reload.
Remove excess ash from the front of the firebox and bring the ashes forward. Place a new load
of wood on, and at the back of the embers. Open the air control completely and close the door.
Raking the coals is useful for two reasons. First, it brings them near where most of the combustion
air enters the firebox. This will ignite the new load quickly. Secondly, the charcoal will not be
smothered by the new load of wood. When the embers are simply spread inside the combustion
chamber, the new load smoulder for a long time before igniting.
Close the air control only when the firebox is full of bright turbulent flames, the wood is charred,
and its edges are glowing.
The heater should not be left unattended during ignition and the fire should not burn at full
intensity for more than a few minutes.
When lighting a new load, the appliance produces a heat surge. This heat surge is pleasant when
the room temperature is cool but can be unpleasant when the room is already warm. Therefore,
it is best to let each load of wood burn completely so that the room cools down before putting
a load of wood back on.
5.5 Removing Ashes
Ash should be removed from the firebox every two to three days of full time heating. Ash should
not accumulate excessively in the firebox since it will affect the proper operation of the appliance.
The best time to remove ash is in the morning, after an overnight fire when the insert is relatively
cold, but there is still a little chimney draft to draw the ash dust into the insert and prevent going
out into the room.
Ashes almost always contain live embers that can stay hot for days and which release carbon
monoxide gas. Ashes should be placed in a tightly covered metal container. The container must
be placed on a non-combustible floor or on the ground well away from all combustible materials.
If the ashes are disposed of by burial in soil or otherwise locally dispersed, they should be kept
in a closed metal container until they are completely cooled. No other waste should be placed
in this container.
NEVER STORE ASHES INDOORS OR IN A NON-METALLIC CONTAINER
OR ON A WOODEN DECK.
CENDRES
ASHES