Hi-Flame Precision III HF910 User manual

Precision III HF910
Free-standing Multi Fuel Non-Boiler Stove
Instruction Manual
www.hi-flame.com
You will need to refer to the serial
number of your stove shown above
should you ever need to make a claim
under the Precision Warranty. You will
also find the serial number, beginning
with HF, on the CE plate at the rear of
the stove as well as on the lid of the
outer packaging.
Published September 2012
Please note This appliance must, at
all times, be operated in accordance
with the instructions to minimise the
amount of smoke produced.
Ref: HF910 / UK-NI-ROI / V1-ND.15-09-12
®
Precision

USER WARNING NOTE
WATCH OUT
!
CARBON MONOXIDE KILLS
Properly installed, operated and
maintained this stove will not emit
fumes into the dwelling.
Occasional fumes from removing
ash and refuelling may occur.
However, persistent fume emission
is potentially dangerous and must
not be tolerated.
If fume emission does persist, then
the following immediate action
should be taken:
• Open doors and windows to ventilate
the room and then leave the premises
• Let the fire go out
• Check for flue or chimney blockage
and clean if required
• Do not attempt to relight the fire until
the cause of the fume emission has been
identified and corrected. If necessary
seek expert advice
The most common cause of fume
emission is flueway or chimney
blockage. For your own safety these
must be kept clean at all times see
page 34.
If the CO alarm (which should be
fitted at the time of installation)
sounds, please follow the advice
above.
Please note: From 1 September 2014
a CO alarm will now be a mandatory
requirement for all stove installations in
the Republic of Ireland.

WATCH OUT
!
CARBON MONOXIDE KILLS
CONTENTS
3
Page
4
5
6
7
7
8
9
10
12
13
14
15
15
16
20
21
22
23
24
28
28
33
33
34
36
37
38
Back Cover
Standard Features
General Dimensions
Technical Data
Introduction
Packing List
Installation Regulations
Important Safety Advice
Assembling the Stove
Smoke Control Areas
Recommended Fuels
Prohibited Fuels
Understanding Fuel Types
Important: First Fires
Burning Wood Logs
Burning Mineral Fuels
Some Simple Tips
Removing Ash
Installation Check-list
Installation General Guidelines
Commissioning
Trouble-shooting
Routine Checks
Standing Down
Routine Maintenance
Annual Service
Service Record
The Precision Warranty
Spares Service
Model Precision III
HF910
Free-standing
Multi Fuel Non-Boiler
Stove
PLEASE NOTE
This instruction manual is also used for
a number of other stove models in the
Hi-Flame product range and therefore
some of the stove photographs and
diagrams used, which are used for
guidance purposes only, may differ
slightly from your new Precision stove.
However, the principles illustrated here
remain the same.
Hi-Flame Fireplace (UK) Limited

4
1
3
5
5
4
2
STANDARD FEATURES
1 Primary Air Control Air which enters
under the grate for burning multi fuels,
(other than wood). Also used at the
beginning of wood fires
2 Pre-heated Secondary Air
Control Air enters at the base of the
stove is pre-heated to ensure the fire-
chamber is not cooled down by new
colder air. This ensures a higher fire-
chamber temperature and therefore a
cleaner, more efficient burn. Controls
the air supply when burning wood
3 Pre-heated Tertiary Air
System Pre-heated
air enters the stove
through jets in the
special cast iron heat
sink at the rear of
the firechamber. This
ensures a much
longer, cleaner burn
from the HF910,
even in the latter
stages of fire cycle
4 Airwash System
Part of the secondary
air control system
which diverts pre-
heated air down
along the front of
the glass to burn off
unwanted dry sooty
particulates and
help keep it clean
5 Top or Rear
Flue Option Simple
to switch depending
on the type of
installation
IMPORTANT
In the interests of safety please
read these instructions carefully
before installing or operating
your new stove. Even if you have
installed or operated stoves before,
manufacturers’ requirements can
vary and can also change with
updates to building regulations.
If installed in a UK Smoke Control
Area this stove must be operated
in accordance with the instructions
to minimise the amount of smoke
produced and it will be illegal to
burn wood in it.

5
GENERAL DIMENSIONS
All dimensions in millimetres

TECHNICAL DATA
GENERAL SPECIFICATION
Model Name Precision III
Model Number HF910
Overall Height 735 mm
Overall Width 605 mm
Overall Depth 494 mm
Net Weight 140 kg
FLUE
Flue configuration top or rear
Flue pipe diameter (6”) 150 mm
Height to centre of rear flue 560 mm
From centre of top flue to back 168 mm
Minimum flue height
from top of stove 4500 mm (15’)
Recommended flue draught 12 Pa
FUEL REQUIREMENTS
Wood Logs:
Moisture content <20%
Maximum Log Length 450 mm (18”)
Maximum Fuel Load 3 kg (6 lb 9 oz)
Multi Fuel:
Authorised Smokeless Fuels
Recommended Fuel Load 3.8 kg (8 lb 6 oz)
Maximum Fuel Load 7.7 kg (16 lb 8 oz)
MINIMUM DISTANCES TO
COMBUSTIBLE MATERIALS
Rear 600 mm
Sides 600 mm
We do not recommend using
combustible mantels (eg wood)
6
PERFORMANCE DATA
FROM CE EN13240 TEST
Wood Logs
(intermittent use):
Nominal Heat Output 10.0 kW
Refuelling Interval 60 minutes
Efficiency (net) 80.3%
Mean CO Emission (at 13%) 0.14%
Mean Flue Gas Temperature 348ºC
Flue Gas Mass Flow 5.7 gs
Smokeless Fuel – Ancit
(intermittent use):
Nominal Heat Output 11.0 kW
Refuelling Interval 2 hrs
Efficiency (net) 71.9%
Mean CO Emission (at 13%) 0.26%
Mean Flue Gas Temperature 418ºC
Flue Gas Mass Flow 6.7gs
Smokeless Fuel – Ancit
(Continuous use):
Nominal Heat Output 11.7 kW
Refuelling Interval 4 hrs
Efficiency (net) 73.6%
Mean CO Emission (at 13%) 0.24%
Mean Flue Gas Temperature 404ºC
Flue Gas Mass Flow 7.6 gs
Tests at nominal output, burning both
wood logs and mineral fuel, were
carried out with a flue draught of 12 Pa.

INTRODUCTION
Thank-you for purchasing this
Precision III stove. We are confident
that with its state-of-the-art
combustion technology it will warm
your home even on the coldest
winter days and provide you with
many years of pleasure.
Before you install or operate your
stove however, please read this
booklet which contains important
safety advice as well as instructions
which will help you make the most
of your new stove.
All users of this stove should be
aware of the contents of this
handbook. If other people are going
to operate the stove then please
keep this booklet handy so that it
can always be quickly referred to.
Never let anyone use the stove who
is unfamiliar with its correct
operation.
7
PACKING LIST
As soon as you receive your new stove
please check that you have a full set of
components as set out in the list below.
In the unlikely event of a shortage,
please report this immediately to the
dealer you bought the stove from.
Never attempt to operate the stove
with missing or damaged components.
Product Information
1 Instruction Booklet
1 Warranty Card
Stove Components
1 Stove Lid
1 Handle Cover
1 Handle Cover Securing Bolt
1 Log Retaining Bar
1 Flue Collar / Bolts (factory fitted on
some models)
Equipment
1 Ashpan and 1 Operating Tool
Tool Bag
1 Safety Mitten
2 Spare Glass Retaining Clips
2 Spare Glass Retaining Clip Screws
1 Spare Rope Seal (for door)
1 Allen key (for door hinges)

8
INSTALLATION
REGULATIONS
You must ensure that your stove is
installed by a recognised competent
person who is appropriately qualified
in the installation of stoves and that
the installation complies with all local,
national and European building
regulations.
In the UK we strongly recommend using
a Hetas registered installer (www.hetas.
co.uk) and in Ireland a registered
installer from INFO – the Irish
Nationwide Fireplace Organisation
(www.fireplace.ie). Your authorised
Precision dealer will also be able to
help and advise you.
For further information on local
Building Regulations please consult:
England & Wales
Building Regulations Document J –
Combustion Appliances and Fuel
Storage Systems
www.planningportal.gov.uk
Scotland
Building Standards (2001) Domestic
www.sbsa.gov.uk
Northern Ireland
The Building Regulations (Northern
Ireland) 2000 / Amendment 2006 /
Amendment No 2 2006
www.buildingcontrol-ni.com
Isle of Man
Building Regulations (2007) –
Isle of Man www.gov.im
Republic of Ireland
Approved Document J – Heat Producing
Appliances www.environ.ie
Other Information Points
The Solid Fuel Association website is
a very good source of practical
information www.solidfuel.co.uk.
For additional useful information and
links to the government websites
above, including informative
downloads, visit The Solid Fuel
Technology Institute website
www.soliftec.com.
The British Flue and Chimney
Manufacturers Association website,
accessed through www.feta.co.uk/
bfcma, produces an authoritative and
informative download Yellow Guide to
solid fuel flues and chimneys.
Buildings Insurance
It is a requirement by some building
insurance companies to inform them of
the installation of a new fixed heating
appliance and a relevant certificate of
compliance produced.
Health & Safety
During the installation of this stove and
any related building works you must
comply with any current Health
& Safety at Work regulations.
Particular care should be taken
regarding potential exposure to
Asbestos-based insulating materials
used as part of an existing appliance
installation. Asbestos has not been used
in the construction of this stove.
When using fire cement always read the
manufacturer’s instructions and avoid
contact with skin and eyes.

• To ensure your safety make sure that
your stove’s installation complies with
all local building regulations’ ventilation
requirements. Low energy houses have
their own particular requirements and
these should be strictly adhered to.
• Do not use flammable liquids to ignite
the fire. In the confined space of the
firechamber there is a real potential to
cause a life-threatening flash flame or
explosion.
• Never over-fire the stove. If any
external parts of your stove glow red
during operation then immediate action
should be taken to reduce the supply
of air to the firechamber through the
Primary and Secondary Air controls
which should quickly limit the intensity
of the fire.
• This stove is CE approved and tested
to EU EN13240 standards in the UK by
Kiwa GasTec. Alterations to its
construction could be potentially
dangerous and will also render your
product warranty void.
• Do not use aerosol products in the
vicinity of the stove when it is in use.
• Check and clean the stove’s flue way
and the top of baffle plate regularly
to help avoid potential blockages (see
page 34).
• Clean your chimney regularly
• This stove does not contain Asbestos.
However, ensure that there is no
possibility of disturbing any asbestos-
based materials during its installation.
For more information on stove
safety please visit
www.stovesafetyfirst.com
9
IMPORTANT SAFETY ADVICE
• Ensure that an approved carbon
monoxide detector (BS EN50291:2001)
is fitted in the same room as the stove.
It should be powered by a battery
designed for the working life of the
alarm. Please note that since October
2010 this is now a requirement under
UK Building Regulations.
• External surfaces including the fire-
chamber door and operating handles,
windows, flue pipes and stove
bodywork will become extremely hot.
Always use the tool provided and avoid
touching these parts of the stove
without proper protection, such as heat
resistant gloves or other protective aids.
• Potentially combustible material or
objects such as soft furnishings should
never be left on or near any of the
stove’s hot surfaces. Ensure that wood
supplies and log baskets are kept at a
safe distance from the stove.
• Never leave children unattended in
the room where your stove is being
operated. Ensure that children are
aware of the potential danger and
make sure that they keep clear of the
stove when it is in operation. Where
children, the elderly or the infirm are
present, always use an approved safety
fireguard (BS6539) to prevent
accidental contact with the stove.
• This stove should not be fitted in a
room with an extractor fan (eg kitchen)
as this will adversely affect the air
quality in the room and could be
dangerous for the room’s occupants. It
will also starve the stove of combustion
air and reduce the stove’s efficiency.

10
ASSEMBLING THE STOVE
Your new Precision stove is extremely
heavy. Always handle with care and
make sure that you have additional
strong help when you move it.
The door and door handle, should
not be used to grip the stove as they
could be damaged from supporting the
stove’s weight. Items, such as the lid
fuel retaining bar and baffle plate, can
be removed to help reduce the weight.
Under no circumstances should the
door be removed as this will invalidate
your Precision Warranty.
• Unpack Remove your new stove from
its recyclable packaging. Retain this
until the stove is installed and is fully
operational. Unfasten retaining wires
and remove any components, including
those inside the ash pan, from inside
the stove
• Inspect Please inspect the stove to
check that it has not been damaged in
transit – never attempt to install a stove
which has been damaged. If damage is
suspected then report this immediately
to your stove dealer
• Check List Study the component
packing list on page 7 and make sure
that you have all of the components
listed before proceeding. Some parts
are contained within the ash pan
• Baffle Plate Check the position of
the baffle plate (sometimes known as
the throat plate) inside the ‘roof’ of the
stove to ensure that it has not moved
during transit. This is a heavy metal
plate which directs flames and helps
retain heat inside the stove. The base of
this plate should sit securely on a small
ledge at the back of the firechamber,
towards the top. The rest of the plate
sits on top of the side firebricks to
maintain it at the correct angle and in
line with the top of these side firebricks.
It is best to fully familiarise yourself
with the baffle plate’s correct location
by practising removing it and re-fitting
it prior to the stove’s installation as you
will need to regularly check the top of
this plate and the access to the flue way
to avoid potential soot build up and
blockages. Once you know how to do
this it is a very easy operation.
See page 34
• Flue Options The HF910 stove
can be top or rear flued. Under no
circumstances should the 150mm (6”)
flue outlet diameter be reduced as this
could be extremely dangerous. Your
new stove is configured for a top flue
at the factory as this will always be the
most efficient choice – if it can be
undertaken safely.
The Precision has a removable lid with a flue out-
let cover plate. This plate should be removed for
top flues and left in place for rear flues. The rear
flue blanking plate should be re-used to seal the
open firebox top flue outlet when rear flueing.

Always use the correct sized Phillips
crosshead screwdriver and be careful
not to damage the bolt heads as these
will be re-used. Remove this plate,
making sure that the fire-resistant
gasket does not get damaged as this
plate and gasket will be re-used to
close off the open top flue outlet. Next,
remove the loose fitted stove lid to
access the top flue outlet and close this
off with the rear plate you have
just removed, ensuring that the fire-
resistant gasket on the base of the plate
makes a good seal. Attach the flue
collar (contained in the ash pan) to the
rear outlet on the firechamber using the
bolts supplied, again ensuring a good
seal is made.
You must ensure that rope gaskets are
positioned correctly to make a good
all-round seal between the collar and
plate. Lubricate the new bolt holes with
machine oil to avoid damaging the
screw threads.
• Handle Assembly Thread the split
washer along the handle bolt. Feed the
bolt and washer through the handle
grip. Use a Phillips crosshead
screwdriver to attach the assembled
grip to the door handle clamp
mechanism on the door, being careful
not to over-tighten.
Your stove is now ready for installation.
• Moving Always lift the stove to finally
position it. Alternatively place the stove
on heavy duty plastic sheeting or thick
floor covering to slide the stove into
position, being careful not to damage
any finished floor surfaces with trapped
grit or building debris.
11
For a top flue outlet remove the loose
fitted stove lid and unfasten the
blanking plate fixing screws underneath
the lid to reveal the flue pipe opening
(see below left). As you will see the flue
aperture is already open on the top of
the firechamber bodywork. When
using the top flue option the lid
blanking plate is no longer needed.
Attach the flue collar (contained in the
ash pan) to the top outlet on the fire-
chamber using the bolts supplied.
Ensure that a good seal is made
between the firechamber surface and
the collar – use fire cement if necessary.
Re-attach the loose fitted lid to the
stove bodywork. The flue pipe can then
be fitted through the lid into the collar.
Neatly apply a seal of fire cement and /
or fire rope to ensure there is no
possibility of a gas or smoke leak.
For a rear fitted flue, remove the
pre-cut shape (see below) on the rear
heat shield which will provide access to
the rear flue outlet sealing plate.
The Precision pre-cut rear heat shield. When using
the rear flue outlet option the cut out can be
easily removed by using a junior hacksaw blade to
cut through the 3 small retaining links.

12
YOUR LEGAL OBLIGATIONS
IF YOU LIVE IN A UK
SMOKE CONTROL AREA
The Clean Air Act 1993
and Smoke Control Areas
Under the Clean Air Act local
authorities may declare the whole or
part of the district of the authority to be
a Smoke Control Area.
It is an offence to emit smoke from a
chimney of a building, from a furnace
or from any fixed boiler if located in
a designated Smoke Control Area.
It is also an offence to acquire an
‘unauthorised fuel’ for use within a
Smoke Control Area unless it is used in
an ‘exempt’ appliance (‘exempted’ from
the controls which generally apply in
the Smoke Control Area).
The Secretary of State for Environment,
Food and Rural Affairs has powers
under the Act to authorise smokeless
fuels or exempt appliances for use
in Smoke Control Areas in England.
In Scotland and Wales this power
rests with Ministers in the devolved
administrations for those countries.
Separate legislation, the Clean Air
(Northern Ireland) Order 1981, applies
in Northern Ireland. Therefore it is
a requirement that fuels burnt or
obtained for use in smoke control areas
have been ‘authorised’ in Regulations
and that appliances used to burn
solid fuel in those areas (other than
‘authorised’ fuels) have been exempted
by an Order made and signed by the
Secretary of State or Minister in the
devolved administrations.
Further information on the
requirements of the Clean Air Act can
be found at the following website:
www.smokecontrol.defra.gov.uk.
Your local authority is responsible for
implementing the Clean Air Act 1993
including designation and supervision
of Smoke Control Areas and you can
contact them for details of Clean Air
Act requirements.
The HF910 Precision III is not
recognised as a Smoke Exempt
Appliance and therefore if you
use this stove in a Smoke Control
Area you must only use approved
smokeless fuels. It will be illegal to
burn wood in it.

– the time between refills. All of this is
providing it is fully seasoned wood.
Never use wet or unseasoned (green)
wood as this will cause nuisance smoke
and a very disappointing fire.
It could quickly result in the build up of
soot and creosote which, because of
the higher temperatures of stove flue
gases, could easily cause a flue or
chimney fire. In addition, burning wet
wood creates other environmental
problems, a less efficient fuel economy
and can eventually clog your flue
system and cowl. It will also reduce the
effectiveness of the stove’s Airwash
system thus causing staining and
blackening of the glass.
Wet or unseasoned would produces the
following poor performance:
• Hard to light fires
• Fires that are difficult to keep going
or to keep burning well
• Smoky fires with fewer flames which
are also of a dull orange colour
• Increased dense grey / blue smoke
from the chimney
• Shorter burn times
• Low heat output
• Dirty glass and firebricks
• Excessive and rapid creosote build-up
in the flue system and chimney
• Unpleasant smoky smells both inside
and sometimes outside the house
Manufactured or finished wood
products, such as plywood and
chipboard, must also be strictly avoided
because of the high chemical adhesive
13
RECOMMENDED FUELS
The Precision III HF910 stove allows the
burning of wood in non-Smoke Control
Areas and approved smokeless multi
fuels only, in Smoke Control Areas. It
must, at all times, be operated in
accordance with the instructions to
minimise the amount of smoke
produced.
The following fuels are approved by
Precision stoves for use in the HF910:
• Wood Logs Only ever use dried, fully
seasoned chopped wood logs with a
moisture content of less than 20%.
Wood which is well seasoned makes
a distinctive ‘clack’ rather than a dull
‘thud’ when knocked together. It will
also feel much lighter than an
unseasoned log. Other indicators
include bark peeling away and cracking
and splitting around the outside.
Ideally wood should be seasoned
outdoors for between 18 to 24 months
– the harder the wood then the longer
the seasoning. It should be stacked off
the ground with plenty of space
between the logs to allow air
movement and with the top covered
to keep rain and snow out. Seasoned
wood will give you approximately 50%
more heat output than the equivalent
unseasoned log.
Most types of hardwood, for instance
Ash (generally regarded as the best),
Birch, Beech, Oak and Elm can be used.
However, avoid woods with a high
resin content. As a rule of thumb, the
heavier the wood, then the greater the
heat output and the longer burn time

14
content used in their production which
will also leave harmful residue inside the
stove and flue system.
For more information about wood fuel
visit the DEFRA funded National Energy
Foundation website Logpile at
www.nef.org.uk/logpile.
• Peat or Turf Do not use in a Smoke
Control Area. Peat is an excellent
cost-effective fuel alternative and
provides a similar calorific heat output
to wood but has a higher ash content
so that you will be required to empty
the ash pan more often. It’s also clean
and easy to handle with low
atmospheric emissions.
• Multi Fuels (Other than wood or
peat). Only burn Authorised Smokeless
Fuels in a Smoke Control Area. Use solid
fuels which are recommended and
approved for use in stoves.
If you cannot burn wood then we
always recommend burning a smokeless
alternative as this is better for the stove
and flue system as well as the
environment. There are many different
brands of high quality smokeless coal
nuggets available in the UK and your
local fuel merchant, preferably a
member of the Approved Coal
Merchants Scheme, will be able to
advise you on those suitable for multi
fuel stoves. You can also find out more
about the various fuel types by visiting
www.hetas.co.uk and
www.solidfuel.co.uk.
PROHIBITED FUELS
Never use your stove like an incinerator.
Burning prohibited ‘fuels’ is an offence
in a Smoke Control Area and could
create nuisance smoke which is also an
offence in non-Smoke Control Areas.
Burning the following ‘illegal’ materials
could also damage your stove and flue
system, as well as render the product
warranties on the stove and flue system
components void.
• Petroleum Coke Never burn
petroleum coke as this burns at a very
high temperature and its continued use
will almost certainly cause irreparable
damage to components such as the
grate, baffle plate and fire bars.
• Bituminous House Coal is not
recommended because it produces
excessive soot deposits, which is not
good for the environment, and also
considerably increases the need for
cleaning the stove and flue system.
• Household Rubbish Printed matter
(excluding very small amounts of
newspaper for starting the fire),
plastic, rubber, lacquered or
impregnated wood, plywood,
chipboard and household rubbish, such
as milk cartons, should also be avoided.
During combustion some of these
materials may develop substances
which could be hazardous to your
health and be harmful to the
environment.
• Flammable Liquids Never use
methylated spirits, petrol or other highly
inflammable liquids for lighting the fire
as these could cause an explosion in the
confined spaces of the firechamber.

UNDERSTANDING HOW
DIFFERENT FUELS BURN
Wood and solid fuels (multi fuels) burn
in different ways and you will need to
understand these differences if you
want to get the best out of operating
your stove.
Basically solid fuels need a flow of
combustion air through the bottom
grate whereas wood does not require
this as its combustion air can be taken
from above the grate. Wood always
burns best on a bed of its own embers
and shouldn’t need to be riddled. On
the other hand, solid fuel requires
riddling to maintain an adequate air
flow from underneath the grate.
Your new stove can burn very well,
or very poorly, depending on how you
light the fire, how you refuel the fire,
and, of course, the type and quality of
the fuel that you are burning. A flue
temperature gauge and log moisture
meter are cost-effective investments
and are highly recommended if you
want to maximise the efficiency of your
stove and fuel.
Wear protective gloves when loading a
burning stove and place logs and other
fuels precisely where you want them by
using heat-resistant tongs. Always open
the stove door gently to avoid
unnecessary air turbulence which could
cause ash or small lighted embers to
be drawn from the fire chamber and
beyond the protective hearth. Never
operate the stove without the fire fence
(or log guard) in position.
The stove is not designed to be
operated with the door open.
15
IMPORTANT: FIRST FIRES
Use smaller and shorter ‘gentle’ fires
the first five or six times that you fire up
the stove, making these progressively
bigger, as this will avoid any potential
thermal shock and allow the steel and
cast iron components to ‘acclimatise’
with each other. Allow the stove to fully
cool down between these fires.
When first using the stove it is normal
to experience paint fumes or see light
smoke rising from some of the stove’s
painted surfaces. During this stage
ensure that the room has additional
ventilation by opening doors and
windows to minimise any adverse
effects.
The hotter you burn the stove the more
intense these fumes will be, which is
one of the reasons that we advise that
you use smaller fires to start with. Every
time the stove reaches a new higher
temperature it may still be possible to
smell these fumes or see some gentle
smoke until the paint work is fully
cured.
If smoke and fumes persist do not use
the stove and immediately consult your
installer, as this may indicate that there
could be a possible problem with the
flue system or installation.

16
BURNING WOOD LOGS
As previously stated wood burns best
on a bed of its own embers which also
forms a barrier that reflects heat and
protects the fire grate from being
damaged. You can therefore leave a
bed of ash in place to create a layer of
approximately 25mm (1”), only
occasionally removing the surplus ash.
The end grain of the wood produces
more of the remaining moisture and
gases so whenever possible point the
log ends away from the glass to help
keep the glass clean.
Fuel Load The logs should be a
maximum of approximately 450mm
(18”) long with a diameter of
approximately 75 –100 mm (3 – 4”).
The recommended maximum fuel load
is 3 kg (6 lb 9 oz).
To get the best out of your stove,
ideally you will need three different
thicknesses of wood log as you build
the fire through each lighting phase:
A Kindling This is generally finely
chopped wood, approximately 5 to
10mm thick (1/4” to 1/2”) from your
supply of logs. Alternatively use dried
twigs or small branches which have also
been fully seasoned
B Lighting Logs These are slightly
bigger diameter logs, approximately
25 to 50mm (1” to 2”)
C Refuelling Logs These should be
approximately 75 to 100mm thick (3”
to 4”). Bigger logs should be split down
to this size
Lighting a Wood Fire
The main difference between smoke
and flame is temperature, so when
lighting a fire you need to get the
temperature in the firechamber as high
as possible as quickly as possible. This
is also critical in creating a good ‘draw’
within the flue system, especially when
it is particularly cold outside.
When flue gas temperatures are below
120°C, creosote tars form within the
gases and the fire will be smoky and
burn with a dull orange flame. Burning
the stove like this for a sustained period
will create unnecessary smoke and not
be good for the chimney or flue system.
1 The Lighting Phase
For best results:
Primary Air – fully open
Secondary Air – fully open
Door – slightly ajar (optional)
Avoid trying to light the fire with
excessive amounts of paper as this
has a very high ash content which can
‘smother’ the ash bed. If you have good
dry kindling or sticks then paper should
A
B
C

2 The First Refuel Phase
For best results:
After 10 minutes...
Primary Air – close completely
Secondary Air – fully open
Door – closed
Once the embers are starting to glow
and the flames start to calm down the
first refuelling can take place. For this
stage use slightly larger pieces of wood
than the lighting wood – but smaller
than the main refuelling wood in the
next phase. The reason for this is that
the embers from the kindling wood are
small and will not hold a high
temperature for too long.
If unnecessarily large pieces of wood
are placed on the embers at this stage
and do not ignite well there is a risk
that the firebox will cool down and the
wood start to smoke. When the first
refuelling wood is burning well (say,
after about 10 minutes from the start)
the Primary air can be completely shut.
3 The Main Firing Phase
For best results:
After 17 or 18 minutes...
Secondary Air – adjust to suit
Primary Air – remains closed
Door – remains closed
Once the embers of the first refuel
phase are glowing then these can be
evenly spread with a poker or
companion tool and the main
refuelling wood can be quickly set.
Wood burns best if the flames have
other wood to ‘play off’. For example a
single dense piece of wood or log will
not burn as well as 2 or 3 smaller logs
of equivalent mass. The more contact
Use the tool provided to adjust the Secondary air
control A – moving it to the left hand side will
reduce the air supply and ‘slow’ the fire down.
B is Primary air – move clockwise to close
A
B
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not be needed at all.
The size of the logs used at each stage
is also important. If the kindling wood is
too large this will not light well and will
be slow to get started. Two handfuls of
smaller pieces of kindling (equivalent
to the weight of typical log) layered in
a criss-cross or ‘wig-wam’ and a small
firelighter will get the fire established
and up to operating temperature
quickly.
If you feel you have a weak chimney
draught, then keeping the stove door
slightly ajar for the first 10 – 15
minutes will assist, after which it should
be closed. This will also help prevent the
build-up of condensation on the door
glass until the glass warms up,
especially if you have not used the stove
for a few days.
During the lighting phase the Primary
and Secondary air settings on the stove
should be fully open.

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the wood has with each other piece,
the hotter the embers will be. 3 or 4
logs tightly packed to each other will
burn longer but at a lower temperature
than loosely criss-crossed logs.
Approximately 2.0 to 2.5kg of wood
logs can be added at this stage. Be
careful not to add too many logs as
they may ‘smother’ the fire. Try to avoid
setting the ends of the logs pointing
towards the glass as this can cause
staining which the Airwash may find
difficult to remove.
Only reduce the Secondary air control
when the wood has ‘carbonised’ and
the fire is burning at a high
temperature. This is when the ash on
the burning wood looks light grey and
virtually covers all of the wood. A flue
temperature gauge will be invaluable.
You will be able to tell when the stove
is at this stage by studying the colour of
the burning surfaces – the ‘lighter’ they
Maximum height of wood fuel load
Maximum fuel load: This should never be higher
than the lowest part of the logo circle in the
tertiary air plate at the back of the firechamber
as shown.
are the better the wood is burning.
If the log surface is predominately
black and / or the flames are a dull
orange then there is still some time to
go before the fire is operating at full
temperature.
Never leave the stove unattended after
refuelling until the flames are well
established on the new logs. Always
load onto a bed of hot embers.
Once the fire is established the flame
pattern can then be adjusted to your
requirements with the Secondary air
(Airwash) control.
Getting the balance right between a
gently burning stove and one that is
burning too slow, creating smoke and
causing the Airwash to fail and
consequently the glass to stain is very
much a matter of trial and error. If you
are burning well-seasoned wood then
a quick ‘blast’ of the stove operating at
‘full throttle’, with Secondary and
Primary air fully open, should quickly
burn off any deposits left from any
slower burning phase.
4 Refuelling
For best results: Just before you refuel...
Primary Air – fully open
Secondary Air – fully open
After loading and when new fuel is
burning well...
Primary Air – close completely
Secondary Air– adjust to suit
Regular, smaller loads are better
because they keep the firechamber at a
higher temperature, without over-firing
it. The higher operating temperature
helps prevent nuisance smoke and
sooty deposits.

to avoid overloading the fire chamber.
Operating in a Smoke Control Area
To meet your legal obligations when
operating this stove in a UK Smoke
Control Area it must be operated
correctly to minimise the amount of
smoke it produces.
• Do not burn wood in this stove – the
Precision III HF910 is not an appliance
exempted by DEFRA for use in a Smoke
Control Area.
• Burn only Authorised Smokeless Fuels.
A list of these can be found at:
www.smokecontrol.defra.gov.uk/fuels.
There are many well-known brands
including authorised products by Bord
Na Mona, Ancit (with which this stove
was CE tested), Homefire, Phurnacite,
Coalite and Taybrite . Experiment with
one or two to decide which works best
for you.
• This instruction book should be left
with the end-user.
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Never overfill the firechamber and also
avoid over-sized pieces of wood which
will ‘slow’ the fire down at the start but
then could lead to over-firing.
Before refuelling open the Primary and
Secondary air supply so that there is a
good strong fire so that the embers are
glowing red which will help the new
fuel to start burning quickly. This will
also ensure that there is no build-up of
harmful gas which could be released
into the room when the firechamber
door is opened.
Rake the embers and spread them out
to make an even bed. You may need
to add some kindling to re-establish
the fire. Add the new wood as before
ensuring that the logs are not tightly
packed.
Newly refuelled wood always requires
some additional air so make sure the
Secondary air is back in the fully open
position after refuelling. Do not adjust
the Secondary air until the fire is
burning well and you can see bright
yellow vigorous flames.
Once the fire is established, usually after
about 5 minutes, close the Primary air
and adjust the flame pattern again to
your requirements with the Secondary
air (Airwash) control.
4 Adding Smokeless Nuggets
If you prefer, you can also add some
smokeless mineral fuel at this stage to
prolong the life of the fire for overnight
burning or to give additional heat when
it is particularly cold. You may also need
to re-open the Primary air to encourage
the non-wood fuel to burn effectively
depending on the load. Be very careful

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BURNING MINERAL FUELS
Do not use in a Smoke Control Area
unless you intend to burn an
Authorised Smokeless Fuel.
See www.smokecontrol.defra.gov.uk
The recommended smokeless fuel load
for the HF910 is 3.8kg (8 lb 6 oz). The
maximum fuel load is 7.7 kg (16 lb 8 oz).
Mineral fuels require much more air
from below the fire for combustion
than wood. This means (depending on
your chimney / flue draught) that
Primary air is generally needed
throughout all of the burning phases.
The Primary air should be fully open at
the start of the lighting phase.
Burning mineral fuels also requires the
grate to be riddled to clear ash so an
adequate supply of Primary air can flow
through it to the fuel load. How much
you need to riddle is very much a
matter of trial and error depending on
the fuel type and burn rate. Always use
a heat resistant tool such as a poker
from a companion set to riddle and
do this as quickly as possible to help
maintain the temperature inside the
firechamber. At the beginning of the
lighting stage the grate should always
be completely clear.
Light your fire in the traditional way
with a small wood kindling fire and
small amounts of your choice of mineral
fuel placed lightly on top making sure
to leave plenty of air space. Once the
mineral fuel is burning well add more
fuel until a there is a good bed of burn-
ing fuel. Avoid stacking too much fuel
against the back and sides of the stove
as this could potentially overheat the
metal components and cause
permanent damage. Ideally, when fully
burning the fire should look like a
shallow dome.
When burning good quality mineral
fuels the Airwash system (Secondary air)
should not be needed to keep the glass
clean, therefore this can be reduced.
The Primary air control should then be
used to adjust the flame pattern. You
may find that a combination of subtle
adjustments to both Primary and
Secondary air controls could best suit
your individual requirements.
When refuelling it is better to use
smaller fuel loads more often which
will provide you with a cleaner, more
efficient burn. Just before refuelling,
riddle the embers to help clear the
ash build-up and re-establish the air
passage underneath the mineral fuel.
Spread the embers evenly with a poker.
Again, open the Primary air to maximise
the heat in the remaining fuel so that
when the new fuel is added it can get
quickly established without ‘damping’
the fire.
Re-adjust the air settings once all the
fuel is burning normally.
Remove the multi fuel ash by emptying
the ash pan regularly – at least once a
day. Do not let the ash build up
under the grate as this will create a
strong hot spot which could eventually
warp or burn-out your grate.