Osburn SOHO OB01522 User manual

READ AND KEEP THIS MANUAL FOR REFERENCE
45841A
Printed in Canada 24-02-2016
INSTALLATION AND OPERATION MANUAL
SOHO
(OB01522 Model)
Dis ribu ed by
Glen Dimplex Aus ralasia
NEW ZEALAND
38 Harris Road, Eas Tamaki, Auckland
Ph: 09 274 8265 Fax [phone]
Email: [e-mail]
www.glendimplex.com.au
AUSTRALIA
Uni 1, 21 Lionel Road
Moun Waverley, Vic oria 3149
Ph: 1 300 554 155 Fax [phone]
Email: [e-mail]
www.glendimplex.com.au
This manual is available for free download on the manufacturer’s web site. It is a copyrighted
document. Re-sale is strictly prohibited. The manufacturer may update this manual from time to
time and cannot be responsible for problems, injuries, or damages arising out of the use of
information contained in any manual obtained from unauthorized sources.

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THANK YOU FOR CHOOSING THIS WOOD FIRE
We ant to congratulate you on your purchase and ish to help you get maximum satisfaction
from your ood fire. In the pages that follo , e ill give you advice on ood heating and
controlled combustion as ell as technical specifications regarding installation, operation and
maintenance of the model you have chosen.
The instructions pertaining to the installation of your ood fire comply ith
AS/NZS 4012/4013 (2014) and AS/NZS 2918:2001 standards.
Please read his en ire manual before you ins all and use your new wood fire. Failure o follow
ins ruc ions may resul in proper y damage, bodily injury, or even dea h. I is impor an ha you
follow he ins alla ions guidelines exac ly.
Consul your local ci y, borough or shire council abou res ric ions and ins alla ions
requiremen s in your area and he need o ob ain a permi .
KEEP THIS INSTRUCTION MANUAL FOR FUTURE REFERENCE.

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Table of con en
PART A - OPERATION AND MAINTENANCE .............................................. 6
1 Safe y Informa ion ............................................................................... 6
1.1 Summary of Operation and Maintenance Cautions and Warnings ...................................... 6
2 General Informa ion ............................................................................ 7
2.1 OSBURN Soho Specifications ................................................................................................. 7
2.2 Zone Heating and Ho to Make it Work for You ................................................................ 10
2.3 The Benefits of Lo Emissions and High Efficiency ............................................................. 10
2.4 Osburn’s Commitment to You and the Environment .......................................................... 11
2.4.1 What is Your Ne Wood fire Made Of? .......................................................................... 11
3 Fuel .................................................................................................... 11
3.1 Materials That Should Not be Burned ................................................................................. 11
3.2 Ho to Prepare or Buy Good Fire ood .............................................................................. 12
3.2.1 What is Good Fire ood? ................................................................................................. 12
3.2.2 Tree Species ..................................................................................................................... 12
3.2.3 Log Length ........................................................................................................................ 12
3.2.4 Piece Size .......................................................................................................................... 12
3.2.5 Ho to Dry Fire ood ....................................................................................................... 13
3.2.6 Where to store ood ....................................................................................................... 14
3.2.7 Judging Fire ood Moisture Content ............................................................................... 14
3.3 Manufactured Logs .............................................................................................................. 15
4 Opera ing Your Wood fire .................................................................. 15
4.1 Your First Fires ..................................................................................................................... 15
4.2 Lighting Fires ........................................................................................................................ 16
4.2.1 Conventional Fire Starting ............................................................................................... 16
4.2.2 The Top Do n Fire ........................................................................................................... 16
4.2.3 T o Parallel Logs .............................................................................................................. 17
4.2.4 Using Fire Starters ............................................................................................................ 17
4.3 Maintaining Wood Fires ...................................................................................................... 17
4.3.1 General Advice ................................................................................................................. 17
4.3.2 Ash Removal ..................................................................................................................... 18
4.3.3 Raking Charcoal ................................................................................................................ 18
4.3.4 Firing Each Ne Load Hot ................................................................................................ 18
4.3.5 Turning Do n the Air Supply ........................................................................................... 19
4.3.6 Building Different Fires for Different Needs .................................................................... 19

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5 Main aining Your Wood Hea ing Sys em ........................................... 21
5.1 Wood fire Maintenance....................................................................................................... 21
5.1.1 Cleaning Door Glass ......................................................................................................... 21
5.1.2 Door Adjustment .............................................................................................................. 22
5.1.3 Replacing the Door Gasket ............................................................................................... 26
5.1.4 Replacing the Glass Gasket and/or the Glass .................................................................. 27
5.1.5 Cleaning and Painting the Wood fire ............................................................................... 28
5.2 Flue and Flue System Maintenance ..................................................................................... 28
5.2.1 Why Flue System Cleaning is Necessary .......................................................................... 28
5.2.2 Ho Often Should You Clean the Flue System? .............................................................. 28
5.2.3 Cleaning the Flue System ................................................................................................. 29
PART B – INSTALLATION ........................................................................ 30
6 Safe y Informa ion ............................................................................. 30
6.1 Summary of Installation Cautions and Warnings ................................................................ 30
6.2 Regulations Covering Wood fire Installation ....................................................................... 31
7 Clearances o Hea -Sensi ive Ma erials .............................................. 31
7.1 Location of the Certification Label ...................................................................................... 31
7.2 Clearances to Walls and Ceiling ........................................................................................... 31
7.3 Floor Protector..................................................................................................................... 33
7.4 Reducing Wall and Ceiling Clearances Safely ...................................................................... 33
8 The Flue Sys em ................................................................................. 35
8.1 General ................................................................................................................................ 35
8.2 Suitable Flue Systems .......................................................................................................... 35
8.2.1 Factory built Insulated Flue Kits ....................................................................................... 35
8.2.2 Masonry Flue Systems ..................................................................................................... 36
8.3 Minimum Flue System Height ............................................................................................. 36
8.4 The Relationship Bet een the Flue System and the House................................................ 37
8.4.1 Why Inside Flue Systems are Preferred ........................................................................... 37
8.4.2 Why the Flue System Should Penetrate the Highest Heated Space ................................ 38
8.5 Installing the flue Connector ............................................................................................... 39

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Appendix 1: Ins alling he Op ional Pedes als (AC01368 or AC01369) ... 41
Appendix 2: Ins alling he Op ional Decora ive Panels .......................... 47
Appendix 3: Ins alling he Op ional Fresh Air In ake Ki ........................ 51
Appendix 4: Ins alla ion and Use of he Op ional Blower and Thermodisc
......................................................................................................... 52
Appendix 5: Ins alla ion of Secondary Air Tubes and Baffle .................. 54
Appendix 6: Exploded Diagram and Par s Lis ........................................ 56
REGISTER YOU WARRANTY ONLINE
To receive full arranty coverage, you ill need to sho evidence of
the date you purchased your ood fire. Keep your sales invoice. We
also recommend that you register your arranty online at
h p://osburn-aus ralia.com/warran y-regis ra ion.aspx
Registering your arranty online ill help us track rapidly the
information e need on your ood fire.

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PART A - OPERATION AND MAINTENANCE
Please see Part B for installation instructions.
1SAFETY INFORMATION
1.1 SUMMARY OF OPERATION AND MAINTENANCE CAUTIONS AND WARNINGS
• HOT WHILE IN OPERATION, KEEP CHILDREN, CLOTHING AND FURNITURE AWAY. CONTACT
MAY CAUSE SKIN BURNS. GLOVES MAY BE NEEDED FOR WOOD FIRE OPERATION.
• USING A WOOD FIRE WITH CRACKED OR BROKEN COMPONENTS, SUCH AS GLASS OR
FIREBRICKS OR BAFFLES MAY PRODUCE AN UNSAFE CONDITION AND MAY DAMAGE THE
WOOD FIRE.
• OPEN THE AIR CONTROL FULLY BEFORE OPENING FIRING DOOR.
• 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 FIRE. KEEP ALL SUCH LIQUIDS OR AEROSOLS WELL AWAY
FROM THE WOOD FIRE WHILE IT IS IN USE.
• DO NOT CONNECT TO ANY AIR DISTRIBUTION DUCT OR SYSTEM.
• DO NOT STORE FUEL WITHIN HEATER MINIMUM INSTALLATION CLEARANCES.
• BURN ONLY SEASONED NATURAL FIREWOOD.
• THE USE OF SOME TYPES OF PRESERVATIVE-TREATED WOOD AS A FUEL CAN BE HAZARDOUS.
• DO NOT BURN:
oGARBAGE OF ANY KIND,
oCOAL OR CHARCOAL,
oTREATED, PAINTED OR COATED WOOD,
oPLYWOOD OR PARTICLE BOARD,
oFINE PAPER, COLORED PAPER OR CARDBOARD,
oSALT WATER DRIFTWOOD, OR
oRAILROAD TIES.
• DO NOT ELEVATE THE FIRE BY USING A GRATE IN THIS WOOD FIRE.
• THIS APPLIANCE SHOULD BE MAINTAINED AND OPERATED AT ALL TIMES IN ACCORDANCE
WITH THESE INSTRUCTIONS.

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2 GENERAL INFORMATION
2.1 OSBURN SOHO SPECIFICATIONS
Model # OB01522
Colour Metallic black
Combustible Hard ood
Recommended heating area* 160 m
2
Test Standard (safety) AS/NZS 2918
Test Standards (emissions) AS/NZS 4012 /4013/4014.1
Optimum efficiency – hard ood 64%
Average efficiency – hard ood 60%
Average emissions – hard ood 1.2 g/kg
Average peak po er – hard ood 9.0 kW
Maximum average po er - hard ood 6.8 kW
Type of blo er (optional) 130 CFM blo er ith variable speed control
Burn Time* 5 to 6 hours
Flue Spigot Diameter 153 mm
Flue system Triple skin flue system
Minimum Flue Height (from floor protector) 4.6 meters
Steel thickness (top) 8 mm
Ceramic glass thickness 5 mm
Maximum Log Length 435 mm
Log loading : Side ays**
Firebox Volume 0,049 m
3
Shipping Weight 157 kg
Baffle Material C-cast
Burn time and heating capacity may vary subject to location in home, flue system draft, flue
system diameter, locality, heat loss factors, climate, fuels and other variables.
Side ays: through the door you see the sides of the logs.

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2.2 ZONE HEATING AND HOW TO MAKE IT WORK FOR YOU
Your ne Osburn Soho ood fire is a space heater, hich means it is intended to heat the area it is
installed in, as ell as spaces that connect to that area, although to a lo er temperature. This is
called zone heating and it is an increasingly popular ay to heat homes or spaces ithin homes.
Zone heating can be used to supplement another heating system by heating a particular space
ithin a home, such as a basement family room or an addition that lacks another heat source.
Although the ood fire may be able to heat the main living areas of your house to an adequate
temperature, e strongly recommend that you also have a conventional oil, gas or electric heating
system to provide backup heating.
Your success ith zone heating ill depend on several factors, including the correct sizing and
location of the ood fire, the size, layout and age of your home and your climate zone. Three-
season vacation homes can usually be heated ith smaller ood fires than houses that are heated
all inter.
2.3 THE BENEFITS OF LOW EMISSIONS AND HIGH EFFICIENCY
The lo smoke emissions produced by the special features inside the Osburn Soho firebox mean
that your household ill release up to 90 percent less smoke into the outside environment than if
you used an older conventional ood fire. But there is more to the emission control technologies
than protecting the environment.
The smoke released from ood hen it is heated contains about half of the energy content of the
fuel. By burning the ood completely, your ood fire releases all the heat energy from the ood
instead of asting it as smoke up the flue system. Also, the features inside the firebox allo you to
reduce the air supply to control heat output, hile maintaining clean and efficient flaming
combustion, hich boosts the efficient delivery of heat to your home.

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The emission control and advanced combustion features of your ood fire can only ork properly
if your fuel is in the correct moisture content range of 15 to 20 percent. See Sec ion 3 of this
manual for suggestions on preparing fuel ood and judging its moisture.
2.4 OSBURN’S COMMITMENT TO YOU AND THE ENVIRONMENT
The Osburn team is committed to protecting the environment, so e do everything e can to use
only materials in our products that ill have no lasting negative impact on the environment.
2.4.1 WHAT IS YOUR NEW WOOD FIRE MADE OF?
The body of your ood fire, hich is most of its eight, is carbon steel. Should it ever become
necessary many years in the future, almost the entire ood fire can be recycled into ne
products, thus eliminating the need to mine ne materials.
The paint coating on your ood fire is very thin. Its VOC content (Volatile Organic Components) is
very lo . VOCs can be responsible for smog, so all the paint used during the manufacturing
process meets the latest air quality requirements ith regards to VOC reduction or elimination.
The air tubes are stainless steel, hich can also be recycled.
The C-Cast baffle is made of an aluminosilicate fibre material that is compressed ith a binder to
form a rigid board. C-Cast can ithstand temperatures above 1093 °c. It is not considered
hazardous aste. Disposal at a landfill is recommended.
Firebrick is mainly composed of silicon dioxide, also kno n as silica, an earth derived product. It is
most commonly found in nature in the form of sand and clay. Disposal at a landfill is
recommended.
The door and glass gaskets are fibreglass hich is spun from melted sand. Black gaskets have been
dipped into a solvent-free solution. Disposal at a landfill is recommended.
The door glass is a 5 mm thick ceramic material that contains no toxic chemicals. It is basically
made of ra earth materials such as sand and quartz that are combined in such a ay to form a
glass at high temperatures. Ceramic glass ill not re-melt in the same ay as normal glass, so it
should not be recycled ith your regular household products. Disposal at a landfill is
recommended.
3FUEL
3.1 MATERIALS THAT SHOULD NOT BE BURNED
• GARBAGE OF ANY KIND,
• COAL OR CHARCOAL,
• TREATED, PAINTED OR COATED WOOD,
• PLYWOOD OR PARTICLE BOARD,
• FINE PAPER, COLORED PAPER OR CARDBOARD,

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• SALT WATER DRIFTWOOD
• MANUFACTURED LOGS CONTAINING WAX OR CHEMICAL ADDITIVES
• RAILROAD TIES
• LIQUIDS SUCH AS KEROSCENE OR DIESEL FUEL TO START A FIRE
3.2 HOW TO PREPARE OR BUY GOOD FIREWOOD
3.2.1 WHAT IS GOOD FIREWOOD?
Good fire ood has been cut to the correct length for the ood fire, split to a range of sizes and
stacked in the open until its moisture content is reduced to 15 to 20 per cent.
3.2.2 TREE SPECIES
The tree species the fire ood is produced from is less important than its moisture content. The
main difference in fire ood from various tree species is the density of the ood. Hard oods such
as gums, Manuka or ironbark are denser than soft oods. Hard ood ill produce long-lasting coal
beds combined to more heat and longer burn cycles.
Old, leaky cast iron ood fires ouldn’t hold a fire overnight unless they ere fed large pieces of
hard ood. That is no longer true. You can successfully heat your home by using less ood and
give the forest a break at the same time.
3.2.3 LOG LENGTH
Logs should be cut about 25 mm shorter than the firebox so they fit in
easily. Pieces that are slightly too long make loading the ood fire very
difficult. The most common standard length of fire ood is 400 mm.
The pieces should be a consistent length, ith a maximum of 25 mm
variation from piece to piece.
3.2.4 PIECE SIZE
Fire ood dries more quickly hen it is split. Large unsplit rounds can take years to dry enough to
burn. Even hen dried, unsplit logs are difficult to ignite because they don’t have the sharp edges
here the flames first catch. Logs as small as 75 mm should be split to encourage drying.

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Wood should be split to a range of sizes, from about 75 mm to 150 mm in cross section. Having a
range of sizes makes starting and rekindling fires much easier. Often, the fire ood purchased from
commercial suppliers is not split finely enough for convenient stoking. It is sometimes advisable to
resplit the ood before stacking to dry.
3.2.5 HOW TO DRY FIREWOOD
Fire ood that is not dry enough to burn is the cause of most complaints about ood fires. The
complaints usually involve a lack of heat and dirty door glass.
Here are some things to consider in estimating drying time:
• fire ood takes a long time to dry
• fire ood bought from a dealer is rarely dry enough to burn, so it is advisable to buy the ood
in spring and dry it yourself
• drying happens faster in dry eather than in damp, maritime climates
• drying happens faster in arm summer eather than in inter eather
• small pieces dry more quickly than large pieces
• split pieces dry more quickly than unsplit rounds
• soft oods take less time to dry than hard oods
• hard oods like gums, Manuka and ironbark can take one, or even t o years to dry fully,
especially if the pieces are big
• fire ood dries more quickly hen stacked in the open here it is exposed to sun and ind; it
takes much longer to dry hen stacked in a ood shed
• fire ood that is ready to burn has a moisture content bet een 15 and 20% by eight and ill
allo your ood fire to produce its highest possible efficiency

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3.2.6 WHERE TO STORE WOOD
This ood fire has been certified to store logs in the pedestal provided that the follo ing
requirements are met:
•The logs must not exceed the inside edge (A) of the pedestal.
•The heat shield baffle (B) under the firebox must never be removed.
•No combustible material can be placed above the heat shield baffle.
Wi h AC01368 pedes al
Wi h AC01369 pedes al
3.2.7 JUDGING FIREWOOD MOISTURE CONTENT
You can find out if some fire ood is dry enough to burn by
using these guidelines:
• cracks form at the ends of logs as they dry
• as it dries in the sun, the ood turns from hite or
cream coloured to grey or yello ,
• bang t o pieces of ood together; seasoned ood
sounds hollo and et ood sounds dull,
• dry ood is much lighter in eight than et ood,
• split a piece, and if the fresh face feels arm and dry it is
dry enough to burn; if it feels damp, it is too et,
• burn a piece; et ood hisses and sizzles in the fire and
dry ood does not.
You could buy a wood mois ure
me er o es your firewood.

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3.3 MANUFACTURED LOGS
Do not burn manufactured logs made of ax impregnated sa dust or logs ith any chemical
additives. Manufactured logs made of 100% compressed sa dust can be burned, but use caution
in the number of these logs burned at one time. Start ith one manufactured log and see ho the
ood fire reacts. You can increase the number of logs burned at a time to making sure the
temperature never rises higher than 246 °C on a magnetic thermometer for installation on ood
fire flue. The thermometer should be placed about 450 mm above the ood fire. Higher
temperatures can lead to overheat and damage your ood fire.
4OPERATING YOUR WOOD FIRE
• NEVER OVERFIRE YOUR WOOD FIRE. IF ANY PART OF THE WOOD FIRE STARTS TO GLOW
RED, OVER FIRING IS HAPPENING. READJUST THE AIR INTAKE CONTROL AT A LOWER
SETTING.
• NEVER LOAD YOUR WOOD FIRE UP TO THE BAFFLE. ALWAYS LEAVE 5 TO 10 CENTIMETERS
TO ALLOW PROPER COMBUSTION THROUGH SECONDARY AIR OPENINGS (NEVER PUT WOOD
ABOVE THE FIREBRICK LINING ON THE FIREBOX). THIS WILL ALSO PREVENT OVERFIRING OF
YOUR WOOD FIRE.
• SHOULD THERE BE A SOOT OR CREOSOTE FIRE IN YOUR FLUE SYSTEM, CLOSE THE AIR
CONTROL COMPLETELY. IMMEDIATELY CALL THE FIRE DEPARTMENT.
4.1 YOUR FIRST FIRES
T o things ill happen as you burn your first fe fires; the paint cures and the internal
components of the ood fire are conditioned.
As the paint cures, some of the chemicals vaporize. The vapors are not poisonous, but they do
smell bad. Fresh paint fumes may also cause false alarms in smoke detectors. So, hen you first
light your ood fire, be prepared by opening doors and/or indo s to ventilate the house. As you
burn hotter and hotter fires, more of the painted surfaces reach the curing temperature of the
paint. The smell of curing paint does not disappear until you have burned one or t o very hot
fires.
Burn one or t o small fires to begin the curing and conditioning process. Then build bigger and
hotter fires until there is no longer any paint smell from the ood fire. Once the paint smell
disappears, your ood fire is ready for serious heating.

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4.2 LIGHTING FIRES
Each person ho heats ith ood develops their o n favorite ay to light fires. Whatever
method you choose, your goal should be to get a hot fire burning quickly. A fire that starts fast
produces less smoke and deposits less creosote in the flue system. Here are three popular and
effective ays to start ood fires.
4.2.1 CONVENTIONAL FIRE STARTING
The conventional ay to build a ood fire is to bunch
up 5 to 10 sheets of plain ne spaper and place them
in the firebox. Next, place 10 or so pieces of fine
kindling on the ne spaper. This kindling should be
very thin; less than 25 mm. Next, place some larger
kindling pieces on the fine kindling. Open the air
control fully and light the ne spaper. If you have a
tall, straight flue system you should be able to close
the door immediately and the fire ill ignite. If your
flue has elbo s or an outside flue system, you may
need to leave the door closed but unlatched for a fe
minutes as the ne spaper ignites and heat in the flue
system produces some draft. Once the fire has
ignited, close the door and leave the air control fully
open.
A conventional kindling fire with paper
under finely split wood.
DO NOT LEAVE THE WOOD FIRE UNATTENDED WHEN THE DOOR IS SLIGHTLY OPENED DURING
IGNITION. ALWAYS CLOSE THE DOOR AFTER IGNITION.
After the kindling fire has mostly burned, you can add standard fire ood pieces until you have a
fire of the right size for the conditions.
4.2.2 THE TOP DOWN FIRE
The top do n fire starting method solves t o problems ith the conventional method: first, it
does not collapse and smother itself as it burns; and second, it is not necessary to build up the fire
gradually because the firebox is loaded before the fire is lit. A top do n fire can provide up to t o
hours of heating or more. The top do n method only orks properly if the ood is ell-seasoned.
Start by placing three or four full-sized split pieces of dry fire ood in the firebox. Next, place 4 or 5
more finely split pieces of fire ood (50 mm to 75 mm in dia.) on the base logs at right angles (log
cabin style). No place about 10 pieces of finely split kindling on the second layer at right angles.
The fire is topped ith about 5 sheets of ne spaper. You can just bunch them up and stuff them in
bet een the kindling and the underside of the baffle. Or you can make ne spaper knots by rolling
up single sheets corner to corner and tying a knot in them. The advantage of knots is that they
don’t roll off the fire as they burn. Light the ne spaper and atch as the fire burns from top to
bottom.

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4.2.3 TWO PARALLEL LOGS
Place t o spit logs in the firebox. Place a fe sheets of t isted ne spaper bet een the logs. No
place some fine kindling across the t o logs and some larger kindling across those, log cabin style.
Light the ne spaper.
4.2.4 USING FIRE STARTERS
Many people like to use commercial fire starters instead of ne spaper. Some of these starters are
made of sa dust and ax and others are specialized flammable solid chemicals. Follo the
package directions for use.
Gel starter may be used but only if there are no hot embers present. Use only in a cold firebox to
start a fire.
DO NOT USE FLAMMABLE LIQUIDS SUCH AS GASOLINE, NAPHTHA, FUEL OIL, MOTOR OIL, OR
AEROSOLS TO START OR REKINDLE THE FIRE.
4.3 MAINTAINING WOOD FIRES
4.3.1 GENERAL ADVICE
Wood heating ith a space heater is very different than other forms of heating. There ill be
variations in the temperature in different parts of the house and there ill be variations in
temperature throughout the day and night. This is normal, and for experienced ood burners
these are advantages of zone heating ith ood.
Do not expect steady heat output from your ood fire. It is normal for its surface temperature to
rise after a ne load of ood is ignited and for its temperature to gradually decline as the fire
progresses. This rising and falling of temperature can be matched to your household routines. For
example, the area temperature can be cooler hen you are active, such as hen doing house ork
or cooking, and it can be armer hen you are inactive, such as hen reading or atching
television.
Wood burns best in cycles. A cycle starts hen a ne load of ood is ignited by hot coals and ends
hen that load has been consumed do n to a bed of charcoal about the same size as it as hen
the ood as loaded. Do not attempt to produce a steady heat output by placing a single log on
the fire at regular intervals. Al ays 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
ood should provide several hours of heating. The size of each load can be matched to the
amount of heat needed.
When you burn in cycles, you rarely need to open the ood fire’s loading door hile the ood is
flaming. This is an advantage because there is more chance that smoke ill leak from the ood
fire hen the door is opened as a full fire is burning. This is especially true if the flue connector has
90 degree elbo s and if the flue system runs up the outside all of the house.
IF YOU MUST OPEN THE DOOR WHILE THE FUEL IS FLAMING, OPEN THE AIR CONTROL FULLY FOR
A FEW MINUTES, THEN UNLATCH AND OPEN THE DOOR SLOWLY.

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4.3.2 ASH REMOVAL
Ash should be removed from the firebox every t o or three days of full time heating. Do not let
the ash build up in the firebox because it ill interfere ith proper fire management.
The best time to remove ash is after an overnight fire hen the ood fire is relatively cool, but
there is still some flue system draft to dra the ash dust into the ood fire and prevent it from
coming into the room.
After ashes have been removed from the ood fire and placed in a tightly covered metal
container, they should be taken outside immediately. The closed container of ashes should be
placed on a non-combustible floor or on the ground ell a ay from all combustible materials
pending final disposal. Ashes normally contain some live charcoal that can stay hot for several
days. If the ashes are disposed of by burial in soil or other ise locally dispersed, they should be
retained in the closed container until all cinders have thoroughly cooled. Other aste shall not be
placed in this container.
NEVER STORE ASHES INDOORS OR IN A NON-METALIC CONTAINER OR ON A WOODEN DECK.
4.3.3 RAKING CHARCOAL
Rekindle the fire hen you notice that the room temperature has fallen. You ill find most of the
remaining charcoal at the back of the firebox, furthest from the door. Rake these coals to ards
the door before loading. There are t o reasons for this raking of the coals. First, it concentrates
them near here most of the combustion air enters the firebox and here they can ignite the ne
load quickly, and second, the charcoal ill not be smothered by the ne load of ood. If you ere
to simply spread the charcoal out, the ne load ill smoulder for a long time before igniting.
Remove ash first, and then rake charcoal towards the front of the firebox before loading so that it
will ignite the new load.
4.3.4 FIRING EACH NEW LOAD HOT
Place the ne load of ood on and behind the charcoal and not too close to the glass. Close the
door and open the air control fully. Leave the air control fully open until the firebox is full of
flames, the ood has charred to black and its edges are glo ing red. Firing each load of ood hot
accomplishes a fe things:
• drives the surface moisture from the ood,
• creates a layer of char on the ood, hich slo s do n its release of smoke,
• heats the firebox components so they reflect heat back to the fire, and
• heats the flue system so it can produce strong, steady draft for the rest of the cycle.

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Although it is important to fire each ne load hot to prepare for a clean burn, do not allo the fire
to burn at full intensity for more than a fe minutes.
DO NOT LEAVE THE WOOD FIRE UNATTENDED WHILE A NEW LOAD IS BEING FIRED HOT.
When you burn a ne load of ood hot to heat up the ood, the ood fire and the flue system,
the result ill be a surge of heat from the ood fire. This heat surge is elcome hen the room
temperature is a little lo er than desirable, but not elcome if the space is already arm.
Therefore, allo each load of ood to burn do n so that the space begins to cool off a little
before loading. Letting the space cool before loading is one of the secrets to clean burning and
effective zone heating.
4.3.5 TURNING DOWN THE AIR SUPPLY
Once the fire ood, firebox and flue system are hot, you can begin to reduce the air supply for a
steady burn.
As you reduce the air supply to the fire, t o
important things happen. First, the firing rate slo s
do n to spread the heat energy in the fuel over a
longer period of time. Second, the flo rate of
exhaust through the ood fire and flue slo s do n,
hich gives more time for the transfer of heat from
the exhaust. You ill notice that as you reduce the air
setting, the flames slo do n. This is your indication
that the ood fire is burning at its peak efficiency.
If the flames get small and almost disappear hen
you turn do n the air, you have turned do n the air
too early, or your fire ood is etter than it should
be. With good fuel and correct air control use, the
flames should slo do n, but should stay large and
steady, even as the air supply is reduced.
4.3.6 BUILDING DIFFERENT FIRES FOR DIFFERENT NEEDS
Using the air control is not the only ay to match the ood fire’s heat output to the heat demand.
Your house ill need far less heat in April than in July to be kept at a comfortable temperature. If
you fill the firebox full in fall eather, you ill either overheat the space or turn the ood fire
do n so much that the fire ill be smoky and inefficient. Here are some suggestions for building
fires to match different heat demand.
4.3.6.1 Small Fires to Take the Chill Off the House
To build a small fire that ill produce a lo heat output, use small pieces of fire ood and load
them crisscross in the firebox. The pieces should be only 75 mm to 100 mm in diameter. After
raking the coals, you can lay t o pieces parallel to each other corner to corner in the firebox and
lay t o more across them in the other direction. Open the air control fully and only reduce the air
after the ood is fully flaming. This kind of fire is good for mild eather hen you are around to

Osburn Soho Ins alla ion and Opera ion Manual
20 ______________________________________________________________________________
tend the ood fire and should provide enough heat for four hours or more. Small fires like this are
a good time to use softer ood species so there ill be less chance of overheating the house.
4.3.6.2 Long Lasting Low Output Fires
Sometimes you ill ant to build a fire to last up to eight hours, but don’t need intense heat. In
this case use smaller pieces of hard ood and place the logs compactly in the firebox so the pieces
are packed tightly together. You ill need to fire the load hot for long enough to fully char the log
surfaces before you can turn the air do n. Make sure the fire is flaming brightly before leaving the
fire to burn.
4.3.6.3 High Output Fires for Col Weather
When the heat demand is high during cold eather, you’ll need a fire that burns steadily and
brightly. This is the time to use your biggest pieces of hard ood fuel if you have it. Put the biggest
pieces at the back of the firebox and place the rest of the pieces compactly. A densely built fire like
this ill produce the longest burn your ood fire is capable of.
You ill need to be cautious hen building fires like this because if the air is turned do n too
much, the fire could smoulder. Make sure the ood is flaming brightly before leaving the fire to
burn. The ood should be positioned in a north/south fashion, that is, from the front to the back
of the firebox.
4.3.6.4 Maximum Burn Cycle Times
The burn cycle time is the period bet een loading ood on a coal bed and the consumption of
that ood back to a coal bed of the same size. The flaming phase of the fire lasts for roughly the
first half of the burn cycle and the second half is the coal bed phase during hich there is little or
no flame. The length of burn you can expect from your ood fire, including both the flaming and
coal bed phases, ill be affected by a number of things, such as:
•
firebox size,
• the amount of ood loaded,
• the species of ood you burn,
• the ood moisture content,
•
the size of the space to be heated,
• the climate zone you live in, and
• the time of year.
The table belo provides a very general indication of the maximum burn cycle times you are likely
to experience, based on firebox volume.
FIREBOX
VOLUME
M
AXIMUM
BURN TIME
<
0.042
cubic
meter
3 to 5 hours
0.042 m
3
to
0.056 m
3
5 to 6 hours
0.056 m
3
to
0.071 m
3
6 to 8 hours
0.071 m
3
to
0.085 m
3
8 to 9 hours
>
0.085 m
3
9 to 10 hours
Long burn times are not necessarily an indication of efficient ood fire operation. When you are
home during the day and able to tend the fire, it is preferable to build a smaller fire that might
provide three or four hours of heating than to fully load the firebox for a much longer burn.
Shorter burn cycles make it easier to match the heat output of the ood fire to the heat demand
of the space.