Hi-Flame HF357i Precision Inset User manual

Model HF357i Precision Inset
Multi Fuel and Wood Burning
Non-Boiler Inset Stove
Instruction Manual
www.hi-flame.com
- -
Published February 2013
Please note This appliance has been independently
CE tested and approved for the burning of wood
and multi fuels and must, at all times, be used in
accordance with these instructions to ensure safe and
efficient operation.
You will need to refer to the serial number of your
stove should you ever need to make a claim under the
Horse Flame Warranty. You will find the serial number,
beginning with HF, on the CE plate attached to the
removable ash lip at the front of the stove as well as
on the lid of the outer packaging.
Write the date the stove was delivered to you below
as this is likely to differ from the purchase date.
Ref: HF357i P / UK-NI-ROI / V3.01-02-13
®
••••
Precision Inset

CONTENTS
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Standard Features
Technical Data
Important Safety Advice
Installation Regulations
Buildings Insurance
Health & Safety
Packing List
Assembling the Stove
Removing the Baffle Plate
Smoke Control Areas
Recommended Fuels
Prohibited Fuels
Understanding Fuel Types
Burning Wood Logs
Burning Mineral Fuels
Overnight Burning
Removing Ash
Installation Check-list
Installation General Guidelines
Fitting Instructions
Commissioning
Important: First Fires
Trouble-shooting
Standing Down
Routine Checks
Routine Maintenance
Horse Flame® Warranty
Spare Parts
Annual Service
Service Record
2
PLEASE NOTE
This instruction manual is also used for a number
of other inset 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
Horse Flame® Precision Inset stove. However, the
principles illustrated here remain the same.
Hi-Flame Fireplace (UK) Limited
INTRODUCTION
Thank-you for purchasing the
Horse Flame® Precision Inset stove.
We are confident that it will warm
your home even on the coldest winter
days and provide you with many years
of pleasurable heat.
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.
The regulation CE plate is attached to the ash lip and concealed
underneath the front of the stove for easy access. Do not remove.

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, remember
manufacturer’s requirements can vary and can
also change with updates to building
regulations. If you are installing this stove in a
UK Smoke Control Area the Precision Inset can
only be fuelled with approved smokeless fuels
– it will be illegal to burn wood in it.
STANDARD FEATURES
1 Primary Air Control Air which enters under the
grate for multi fuel burning and to help get a wood
fire started
2 Secondary Air Control Air which enters at the top
of the fire chamber to ensure a cleaner burn and
effective wood burning (pull out to open)
3 Airwash System Part of the secondary air control
system which diverts hot air down along the front of
the glass to burn off unwanted sooty particulates and
help keep it clean
3
TECHNICAL DATA
General Specification
Model Name Precision Inset
Model Number HF357i
Dimensions (mm): Facia H605 W490 D95
Dimensions (mm): Firebox Ext H515 W380 D175
Net Weight 83 kg
Gross Weight (packed) 95 kg
Data from CE Test EN13229
Fuel Mineral Fuel & Wood Logs
WOOD
Nominal Heat Output 4.9 kW
Test Duration (approx) 1.02 hrs
Efficiency (net) 75.2%
Mean CO Emission (at 13%) 0.15
Mean Flue Gas Temperature 302ºC
Flue Gas Mass Flow 4.8 g/s
ANCIT (mineral fuel)
Nominal Heat Output (wood) 4.8 kW
Test Duration (approx) 3.99 hrs
Efficiency (net) 68.3%
Mean CO Emission (at 13%) 0.21
Mean Flue Gas Temperature 312ºC
Flue Gas Mass Flow 6.3 g/s
Minimum Distance to Combustible Materials
Top (shelf) 600 mm
Sides 250 mm
Flue
Flue configuration top only
Flue pipe / liner diameter 150 mm (6”)
Minimum flue height
from base of stove 4500 mm (15’)
Wood Fuel Requirements
Wood Logs: Moisture content <20%
Maximum Log Length 250 mm
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3
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4
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 this is now a
requirement under UK Building Regulations.
• External surfaces including the fire chamber door
and operating handles, windows 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. See Minimum Distance to Combustibles page 3
• 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 effect
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.
• To ensure your safety make sure that your stove’s
installation complies with all local, national and
European building regulations’ ventilation requirements.
Low energy houses have their own particular
requirements and should be strictly adhered to.
• Do not use flammable liquids to ignite the fire. In
the confined space of the stove’s fire chamber 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 combustion air to the fire chamber 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 EN13229
standards in the United Kingdom by GASTEC at CRE
of Stoke Orchard, Gloucestershire. 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 the baffle plate regularly to help avoid potential
blockages.
• Clean your chimney regularly.
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).
For further information please consult:
England & Wales
Building Regulations Document J (revised October
2010) – 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
For additional useful information and links to the
government websites above, including informative
downloads, visit www.soliftec.com.
The Solid Fuel Association website is also a very good
source of practical information and downloads
www.solidfuel.co.uk.
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. Always use
protective gloves and use the tool when adjusting the
air controls.

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
A This Instruction Booklet and Warranty Card
B Stove Serial Number
Stove Components
C Handle Cover and Handle Cover Securing Bolt
D Locking Bolt and Retaining Clamp for top fixing
E Outer Flue Spigot / Plate
F Ash Lip
G Screw and Anchor for base fixing
H Fire Grate and integral Log Bar (in place)
I Cast Iron Firebricks – Left, Right and Back (in place)
J Baffle Plate (Located inside roof of fire chamber)
Equipment
K Shaped Ash Pan
L Operating Tool
Tool Bag
M Safety Mitten
G Spare Glass Retaining Clips
G Spare Glass Retaining Clip Screws
G Allen key (for door hinges)
M Spare Door Rope Seal
ASSEMBLING THE STOVE
Your new inset 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 never be used to
grip the stove as they could be damaged from
supporting the stove’s weight. Items, such as the cast
iron fire bricks, fire grate and baffle plate can all be
easily removed to help reduce the weight. Under no
circumstances should the door be removed as this will
invalidate your Horse Flame® Warranty.
Always lift the stove to finally position it.
Alternatively it may be possible to 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 or decorative hearth
surfaces with trapped grit or building debris.
• 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.
F
III
J
D
EC
H
KM
G
B
L
A
5

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• Check List Study the Packing List on page 5 and
make sure that you have received all of the
components listed before proceeding. Some
components are contained within the ash pan or will
already be fitted to the stove.
• 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.
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 right
• Flue spigot plate To maximise efficiency the HF357i
inset stove has been designed to work best in
conjunction with a 150mm (6”) flexible flue liner
connected to the purpose-designed spigot / plate
housed on top of the stove. To avoid soot build-up
on the stove bodywork, which could potentially ignite
and cause a chimney fire, we therefore we strongly
recommend that a liner is always used. Should it not
be possible to fit a liner then the householder should
ensure that the chimney is regularly swept and if
possible the stove removed at the same time so that
the top can be thoroughly cleaned.
• Ash Lip The ash lip is simply fitted to the installed
stove by positioning it at the front and pushing it
underneath to make a snug fit. It can then be easily
removed for cleaning the hearth.
• 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 inset stove is now ready for installation.
REMOVING THE BAFFLE PLATE
Regular checking of the baffle plate will ensure that
the stove’s flueway stays clear of soot as well as its
continued safe and efficient operation. If you have
never owned a stove before it is important to
understand how critical this aspect of operating a
stove is. As stated previously it is best to familiarise
yourself with this before the stove is installed. With
the Precision® Inset there are no fixing brackets, bolts
or fire bricks to remove – simply put your hand inside
the ‘roof’ of the fire chamber and push upwards. This
will release the plate which should then be pulled
forward and dropped down inside the stove ready for
inspection and cleaning.
To replace the baffle simply reverse the operation
– ensuring that the two positioning lugs (A) slide into
the retaining brackets (B) on the left and right sides
of the flueway aperture. The plate should be pushed
all the way to the back of the stove so that the final
central positioning lug (C) fits in the bracket (D).
A
B
AA
C
D
C
The view of the
fitted baffle
from the top
(outside)
A
B

UK SMOKE CONTROL AREAS
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 burn an
‘unauthorised fuel’ (ie non-smokeless fuel) in a Smoke
Control Area. It is a legal requirement that fuels burnt
or obtained for use in Smoke Control Areas have been
‘authorised’ and officially designated “Smokeless
Fuels’. Wood log are not classified as a Smokeless Fuel
and therefore should not be burned in the Precision
Inset stove if it is located in a building within a Smoke
Control Area. In such a case you must only use an
authorised Smokeless Fuel.
Further information on the requirements of the Clean
Air Act can be found here:
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.
Even if you don’t live in a Smoke Control Area it is
still the householder’s legal responsibility not to cause
nuisance smoke. Your inset stove therefore should,
at all times, be operated in accordance with these
instructions to which have been written to help you
minimise the amount of smoke produced from your
stove.
RECOMMENDED FUELS
Please note If you live in a UK Smoke Control Area
you must only burn approved smokeless fuels. The
following fuels are approved by Horse Flame® for use
in the HF357i inset stove:
• 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 – 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.
Its use 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 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’ Peat is an excellent cost-effective fuel
alternative and provides a similar calorific heat output
to wood. It’s also clean and easy to handle with low
atmospheric emissions. However, you must ensure
that the peat is kept thoroughly dry as it absorbs and
retains unwanted moisture very easily.
Peat has traditionally been used as a heating fuel in
both Scotland and Ireland and you can find out more
by visiting these suppliers’ useful websites – �www.
peatheat.co.uk (Scotland) and www.bnm.ie/fuels
(Ireland).
• Multi Fuels (Other than Wood or Peat) If you
cannot burn wood then we recommend burning a
smokeless alternative, such as smokeless nuggets, as
this is better for the stove and flue system as well as
the environment. Your stove is also approved to burn
coal – however, we do not recommend prolonged use
of bitumous house coal because of the excessive soot
it produces. There are many different brands of high
quality smokeless coal nuggets available in the UK and
7

Ireland. The most popular include Phurnacite, Taybrite,
Ancit and Homefire.
Your local fuel merchant will be able to advise you on
the best types of coals suitable for multi fuel stoves,
as well as natural mineral fuel alternatives such as
anthracites which burn cleanly. The following fuel
merchant’s website also has good descriptions of the
comparative benefits that the brands listed above
have to offer – www.coalproducts.co.uk.
You can also find out more by visiting the Hetas
website www.hetas.co.uk.
PROHIBITED FUELS
Never use your stove like an incinerator. Burning
prohibited ‘fuels’ in a Smoke Control Area is illegal.
Burning the following materials could also damage
your stove and flue system, rendering 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 thus considerably
increases the need for frequent cleaning of 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 fire chamber.
UNDERSTANDING HOW
DIFFERENT FUELS BURN
Wood and solid or mineral fuels (multi fuels) burn in
different ways and you will need to understand these
differences if you are a newcomer to wood burners
and multi fuel stoves.
Putting it simply, mineral fuels, such as coal or
smokeless nuggets, need a flow of combustion air
through the bottom grate which is known as Primary
Air, whereas wood fuel works much better when its
combustion air is taken from above the grate. This
source of air is known as Secondary Air. Wood always
8
burns best on a bed of its own embers and the ashes
shouldn’t need to be riddled. Again mineral fuels
differ because they need combustion air from below
the grate therefore needs to be riddled to keep the air
passage clear.
See the section below to help you understand how
to control the different types of combustion air that
wood and mineral fuels need.
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 log moisture meter is a
cost-effective investment if you want to maximise the
efficiency of your stove and wood fuel.
Wear protective gloves when loading a burning stove
and place the fuel precisely where you want it in the
fire chamber by using heat-resistant tongs. Always
open the stove door gently to avoid unnecessary air
turbulence which could cause fly ash or small lighted
embers to be drawn from the fire chamber and
beyond the protective hearth.
The stove is not designed to be operated with the
door left open continuously – this will reduce its
operating efficiency and it will consume more fuel
very quickly and produce less heat.
CONTROLLING THE COMBUSTION AIR
Your Precision Inset stove has two simple air controls:
1 Primary Air Control This is the large control knob
in the centre at the base of the stove. Primary Air is
required when burning mineral fuels (and to quickly
aid the supply of air during the initial combustion of
wood). Turn it anti-clockwise to open and add air.
2 Secondary Air Control This is the silver control
knob on the right hand side of the stove – pull it out
to open the air supply. Secondary air is needed when
burning wood and is not needed when burning
mineral fuels (unless it is to maximise the air supply to
aid the initial combustion).

9
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 from the
grate. Ash should still be regularly removed from the
ash pan. Once you have lived with your stove for a
while you’ll soon get to know how often you should
do this.
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 Ideally the logs should be
approximately 225 (9”) long and a typical fuel load
should weigh 1.0 – 1.5kg (2.2lb – 3.3lb).
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:
1 Kindling This is generally finely chopped wood, ap-
proximately 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
2 Lighting Logs These are slightly bigger diameter
logs, approximately 25 to 50mm (1” to 2”)
3 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 tem-
perature, so when lighting a fire you need to get the
temperature in the fire chamber 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 (bottom control) – fully open
Secondary Air (top control) – fully open (pull out)
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 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 well
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 Sec-
ondary air settings on the stove should be fully open.
2 The First Refuel Phase
For best results:
After 10 minutes
Primary Air (bottom control) – close completely
Secondary Air (top control) – fully open (pull out)
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 quickly 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 off and
the shaker grate closed for increased efficiency.
3 The Main Firing Phase
For best results:
After 17 or 18 minutes –
Secondary Air (top control) – adjust to suit
Primary Air (bottom control) – 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 larger 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 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 1.0 to 1.5kg of wood logs can be
added at this stage. Be careful not to add too many
logs as they may ‘smother’ the fire or cause the stove
to over-fire.
Try to avoid setting the ends of the logs pointing
towards the glass as this is where some of the gases

10
and moisture from the logs escapes and 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. You will be able to tell when the stove is at this
stage by studying the colour of the burning surfaces
– the ‘lighter’ they 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.
Avoid leaving 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 top
Secondary air (Airwash) control.
Getting the balance right between a gently burning
stove and one that is burning too slowly, 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 (bottom control) – fully open
Secondary Air (top control) – fully open (pull out)
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 fire chamber at a higher temperature, without
over-firing it. The higher operating temperature helps
prevent nuisance smoke and sooty deposits.
Never overfill the fire chamber 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 fire chamber 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 addi-
tional 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.
If the new wood fuel is slow to catch alight, even with
the Primary and Secondary air fully open then you
could open the stove door slightly tom provide
additional combustion air and until strong vibrant
flames are established. This should only take a
matter of a minute or so and on no account should
the stove be left unattended while this is happening
as the stove could very easily over-fire.
Some simple wood burning tips
1 Small regular loads when refuelling will produce a
more efficient and cleaner burning performance.
2 Avoid burning large amounts of wood with the
Secondary air supply turned down as this will reduce
the effectiveness of the Airwash system, as well as
produce excessive smoke and create potential
creosote build-up.
3 Burn on a high output for approximately 30 minutes
each day to ‘burn off’ any potential soot and creosote
build-up – but be careful not to over-fire the stove.
4 Never overload the stove – it will be smoky and
inefficient as well as very slow to establish a good
burn and could eventually possibly over-fire when it
does get going.
5 Bright vibrant flames and a clean fire chamber
indicates that your stove is operating well.
BURNING MINERAL FUELS
Mineral fuels require much more combustion air from
below the fuel load than wood. This means (depend-
ing on your chimney / flue draught) that Primary air
(bottom control) is generally needed throughout all of
the burning phases. The Primary air control should be
in the fully open position at the start of the lighting
phase (you may also need to leave the stove door
open slightly). Burning mineral fuels also requires the
grate to be riddled more often to allow the free flow
of combustion air from the Primary air control.
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 additional fuel until a there is a
good bed of burning fuel. Avoid stacking too much
fuel against the back and sides of the stove as this
could potentially overheat the stove’s components and
cause permanent damage. Ideally, when fully burning
the fire should look dome-shaped.
When burning good quality mineral fuels the Airwash
system (Secondary air) should not be needed to keep

11
the glass clean, therefore Secondary air (top control)
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 air
controls may 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 after refuelling, open the Primary air (bottom con-
trol) to maximise the combustion air delivered to the
remaining fuel so that when the new fuel is added it
can get quickly established without ‘damping’ the fire.
Spread the embers with a poker just before adding
the fuel. Re-adjust the air settings once all the fuel is
burning normally.
Empty the ash pan regularly – at least once a day and
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. It will also eventually limit the
flow of Primary combustion air and could affect the
stove’s performance.
OVERNIGHT BURNING
The Precision Inset stove is designed to allow over-
night burning. To do this put a good fuel load into the
stove and allow it to burn for about 15 – 20 minutes
in the normal way. Then limit the Secondary air supply
and make sure when burning wood that the Primary
air is closed.
The best setting to achieve the best burn and cleanest
glass will be a matter of experimentation. For mineral
fuels close the Secondary air supply and minimise the
Primary air.
When you return to your stove, fully open both air
controls until you have a good fire and then set to
normal operating levels. Do not add fuel until the
firebed is hot and red, then add a little for the first
time and allow it to ignite properly before adding
more. During overnight burning the stove glass will
blacken but if dry fuel has been used and a hot fire is
established again this should quickly burn off.
REMOVING ASH
Remember, you do not need to riddle wood ash
during firing, but possibly only at the start when some
Primary air is needed to aid the initial combustion.
Riddling allows mineral fuel ash to fall into the
collection pan below the fire bed to help maintain a
flow of Primary combustion air to the fuel. The ash
pan should never be allowed to over-fill as this will
limit the Primary air flow and could cause excessive
heat build-up which could eventually warp or burn
out the grate.
Locate the operating tool in the slot at the front of
the ash pan to make a handle and lift the pan from
the stove. For safety reasons ash should be removed
when the stove is cold. If this is not always possible
then extra care should be taken and decorative and
combustible surfaces, such as laminate floors or
carpets, should be protected against potential
accidental spillage. Even if the ash appears to be cold
protective gloves should be worn and the refuse ash
placed in a non-combustible container. The ash could
still be hot with the possibility of hidden live embers
As you remove the ash from your home ensure that
it is covered to protect it from any draught or wind
which could blow the ash out of your container.
The forked end of the tool is inserted underneath the ash pan grip
as shown above to create the ash pan handle.

12
INSTALLATION CHECK-LIST
This information is intended to outline the general
principles of installing your inset stove. However, as
each installation will vary and must comply with local,
national and European building regulations, which
could be different from country to country, it is
unfortunately not possible for these guidelines to be
comprehensive.
Legal Requirements
Please note that, not only is it a legal requirement to
ensure that your stove installation complies with all
applicable building regulations, it is also a
requirement of your Warranty that the stove is
installed by a competent person such as a Hetas or
INFO registered installer who will be fully aware of any
building and safety regulations which apply to stove
installations in your location.
Inset Stove Location Checklist
• The existing constructional hearth (the main part of
the hearth) is suitably constructed and is of a
thickness that conforms to all applicable building
regulations.
• The back hearth (the part of the hearth that the
inset stove sits upon and which is usually within the
fireplace recess or opening) is also suitably constructed
and conforms to all applicable building regulations.
• The superimposed hearth (the thinner, usually
decorative surface, which sits on the constructional
part of the hearth) is suitably constructed and con-
forms to all applicable building regulations.
• The fireplace recess or opening is suitably
constructed and conforms to all applicable building
regulations and can accommodate the stove along
with the safe minimum operating distances required.
• Any adjacent walls, next to which a stove is
installed, are of a suitable thickness and are of non-
combustible material and conform to all applicable
building regulations.
• The air supply is sufficient for full combustion of the
stove’s fuel and the health and safety of the room’s
occupants. Any extractor fans inside the room should
be removed or permanently disabled. Note that in the
UK stoves above 5kW output require a non-closable
dedicated air supply within the room which must
conform to applicable building regulations. The
HF357i Precision® Inset stove has been officially rated
at 4.9kW output when burning wood and 4.8kW
when burning mineral fuel.
• The chimney is of sufficient height, is suitably
constructed and is in good condition and conforms
to all applicable building regulations regarding stove
installation. The minimum flue height required for the
Precision® inset is 4.5 metres (15’) from the hearth to
the top of the chimney terminal.
• The chimney has been swept and tested prior to
installation.
• The proximity of all combustible materials to the
intended stove installation conforms to the minimum
requirements outlined within this handbook as well
as local, national and European building regulations,
whichever is the greater. A combustible material is
anything which can burn once it gets hot enough
and includes skirting boards, wooden fire surrounds,
wooden mantles, wallpaper, fabrics and floor
coverings. Remember these materials could be con-
cealed behind other materials which on the surface
may appear to be non-combustible, for example, stud
partitioned walls. It also worth noting that heat-
resistant materials will eventually combust should they
inadvertently reach the required higher combustion
temperatures.
Important Minimum Distances For This Stove
The minimum distances to combustible materials for
the HF357i Precision® Inset are as follows:
Top (eg mantel shelf) 600 mm
Sides (eg fire surround) 250 mm

13
INSTALLATION: GENERAL GUIDELINES
Please refer specifically to current building regulations
which apply to your country or region Adopt
whichever provides the highest / safest margin.
The Hearth
The hearth should be made of solid non-combustible
material, set on a firm and level base and should be at
least 125mm (5”) thick. This can include the thick-
ness of any non-combustible floor under the hearth
or non-combustible decorative surface. It must be
capable of supporting the weight of the stove (when
loaded) along with any attached flexible flue liner
which may bear down on the stove. This hearth must
conform to local building regulations which may vary
from country to country.
In England and Wales there is a minimum requirement
for the hearth to project 500mm (20”) in front of any
brick or stone recess and 150mm (6”) at each side of
the recess. The hearth should extend by a minimum
of 225mm (9”) from the front of the stove (which
includes the edge of the ash lip). As a general rule it is
best to extend the hearth to at least 75mm (3”)
beyond the furthest out-swing of the stove door if
possible to avoid any potential live ash held on the
inset door falling on to combustible flooring or floor
coverings. If the top of the hearth and any combus-
tible floor coverings are level with each other then a
retaining fender should be fitted to warn occupants of
the hearth area. Alternatively, a 28mm (1.1”) change
in level provided by a decorative non-combustible
material such as stone, marble, granite, ceramic tiles
etc could be used.
Please note that some materials, such as marble, may
not be suitable when used in a single sheet. This may
prove problematic if, for example, the inset stove is
being installed within an existing fire surround which
features a one-piece back panel which the inset stove
is intended to sit inside. Non-combustible fire
surrounds intended for use with solid fuel open fires
and stoves feature smaller panels pieced together
which allow space for expansion when hot. Your stove
dealer or installer should be able to advise you about
the suitability of an existing fire surround.
The ‘Fireplace’
The stove must be sited within a brick or stone fire-
place recess. It is unsafe to use this inset stove as a
free-standing stove.
The fireplace side and rear walls should be at least
75mm thick and made of non-combustible brick or
stone. Any gaps at the back and sides of the stove
and the fireplace aperture should be filled with non-
combustible insulation material such as rockwool or
vermiculite. This will not only improve the efficiency of
the stove but also help avoid the potential build-up of
combustible soot along the sides – this is an especially
important requirement if you are not using a flue liner.
Flue Draught
The minimum flue draught requirement for the
HF357i Precision® Inset is 4.5g/s.
The Chimney, Flue and Flexible Liners
Other appliances should not share or be connected to
the same flue system or chimney.
Generally speaking, the chimney or flue terminal
must be above the height of the apex of the building
and any other obstructions, such as trees, which are
within 3m (10’) of the flue terminal. Failure to do this
could affect the efficiency of the stove and may also
cause unwelcome down draughts which would mean
potentially dangerous flue gases could be emitted into
room.
If you are using an existing chimney and it has been
checked for condition and suitability (see below), in
the interests of safety you must ensure that it is swept
before the stove is installed, even if it has never been
used or you intend to use a flexible liner. To find a
local registered sweep visit The National Association of
Chimney Sweeps at www.chimneyworks.co.uk or the
Guild of Master Chimney Sweeps at
www.guildofmasterchimneysweeps.co.uk.
The recommended minimum height for the chimney
/ flue system from the top of the hearth base to the
top of the chimney terminal is 4.5m (15’). If this is not
possible then a ‘spinner’ type cowl, to compensate for
any potential limited up-draught, should always be
specified and specialist advice sought on the correct
type.
Under no circumstances should the stove’s 150mm
(6”) diameter flue be reduced in any part of the flue
system as this could cause a build-up of dangerous
carbon monoxide gas.
When your new inset stove is installed with a flexible
flue liner it should be possible to sweep the chimney
through the stove by simply removing the baffle plate
inside the ‘roof’ of the stove. However, if you do not
use a liner the installer should, if possible, provide an
alternative means, such as a soot door with adequate
air-tight seal, in the chimney wall to be able to clean
the whole of the chimney / flue system.
Since stoves create flue gases at a much greater
temperature than those produced by an open fire or
gas appliance it does not necessarily follow that your
chimney will function adequately (or safely) when
your new stove is installed. The best way to ensure
that you have a fully functioning flue system is to fit
an approved flexible multi fuel flue liner.
Horse Flame strongly recommend fitting a chimney
liner for the following reasons:
• A flue liner is a major ‘quantifiable’ component in
a total and fully functioning flue system. As such it
will provide a consistent flue draught from the stove
through to the chimney terminal and when back-filled

14
with vermiculite will deliver much needed insulation
to keep flue gases as hot as possible which will help
minimise the amount of smoke produced. It will also
improve the stove’s operation with greater control
over the fuel burn rate and improve environmental
and fuel efficiency.
• Your existing chimney could leak smoke, fumes and
potentially dangerous ‘invisible’ carbon monoxide into
other parts of the building.
• Condensation or creosote ‘tar’, often associated
with burning wood, could eventually seep through the
walls, particularly if they are made of old or porous
brick and / or are jointed with lime mortar, eventually
causing unsightly stains on decorative coverings.
• Stoves work best with the correct draught. Pre-1965
chimneys which have been built for open fires have
larger (and irregular shaped) voids than those best
suited for a modern stove and thus could reduce the
effectiveness of the flue draught by making the flue
too cold and difficult to warm. This is a particular
problem if the chimney breast is on an outside wall
and / or is subject to a strong prevailing wind.
• The interior surfaces of older flues could be eroded
and also have rough surfaces which could cause
resistance to the smooth flow of gases and
consequently result in poor up-draught.
• Unfortunately many houses built since 1965 with
clay or concrete chimney liners suffer from these
being poorly installed, either through being fitted the
wrong way up or not receiving an appropriate
application of mortar to make a complete seal on
each joint. Even though not particularly old, this could
still potentially cause leaking smoke and fumes or
condensation stains
Your approved installer will be able to advise you on
the suitability of your chimney after undertaking a
thorough inspection and smoke test. Any solid fuel
flexible liner which is specified should be double
skinned stainless steel, either 904L or 316Ti grade and
be CE marked and / or Hetas Approved.
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.
The Chimney Terminal
The existing chimney pot or terminal must be suitable
for stove installation and should not restrict the smoke
and fumes from the stove. It must provide at least the
same outlet area as the flue pipe. It may be that your
existing chimney terminal has been replaced with a
ventilating terminal if the fireplace has been closed off
at some point and this will need replacing.
Your installer will be able to advise you on the correct
specification of any new cowl or terminal. Cowls have
the additional advantage of limiting rain entering the
flue system which could cause the inside of the stove
to rust when it is not being used, particularly during
the long periods outside the heating season.

15
FITTING INSTRUCTIONS
Fitting the flexible liner spigot plate
An outer flue spigot plate is provided to fit to the top
of stove if you are using an approved flexible liner.
The flue liner should be in place inside the chimney
and securely attached to the spigot plate using the
two pr-drilled screw holes and sealed with fire cement
and / or fire rope before you finally position and fix it
to the inset stove.
The spigot fits around the flue liner so that any
potential creosote will run down the inside of the liner
and then into the stove rather than cause a build-up
on top of the stove bodywork which could
eventually leak and cause an unsightly mess and
possible fire hazard. The spigot / liner joint should be
sealed with fire cement and / or an appropriate fire
resistant rope or gasket.
The spigot can then be easily bolted into place from
inside the stove once the stove’s baffle plate has been
temporarily removed. See diagram 1 below
Outer Flue
Spigot Plate
Flexible liner fits inside
collar and is secured
with two self-tapping
screws (not supplied)
Pre-drilled screw
holes on sides
Two bolts are used to secure the
spigot plate to the flueway
aperture
Inside the stove:
The two bolts are used
to clamp the spigot plate
to the flueway aperture
Remember: The flexible
liner should be dropped
inside the chimney and the
spigot plate secured first

16
Back-filling the chimney and lining should only be
undertaken when the stove is securely fixed in its final
position.
Insulating at the sides and back of the stove
If you are not using a chimney lining then any gaps at
the back and sides of the stove and the fireplace
aperture should be filled with non-combustible
insulation material such as rockwool or vermiculite.
This will not only improve the efficiency of the stove
but also help avoid the potential build-up of
combustible soot along the sides – this is an especially
important requirement if you are not using a flue liner.
Some installations may require you to do this by
removing the stove baffle plate and feeding the
insulating material through the stove flueway and
then manipulating it with your hand so that it
completely fills the voids at the sides and back of the
inset stove.
Attaching the stove to the fireplace
There are three ways that the Precision® inset stove
can be secured to the fireplace or fire surround
depending on the particular opening. To ensure that
you create a firm and safe fix it may be appropriate to
combine two of these methods.
1 Base fixing Firstly, remove the ash pan and grate
carrier. You will see a pre-drilled hole in the centre of
the base of the stove. When using this method,
carefully push the insert into position, locating it
precisely in the fireplace opening before marking the
position of the drill hole on the hearth through the
stove base. Allow for some compression of the rope
seal at the back of the stove to ensure a good seal
between the stove and the fireplace front. Remove
the stove and then drill an 8mm diameter hole in
the hearth. Fit the steel plug (or alternative) in the
hole and carefully re-locate the stove. Fix the screw
through base hole. Be sure to use the correct drill bit
so as not to damage or crack any decorative hearth
plate. See below
2 Clamp fixing There is a specially designed
locking screw and clamping bar supplied with your
new stove. To use this method remove the fire bricks
which will then allow you remove the baffle plate
inside the top of the stove by sliding it forward and
dropping it down and out of the way.
Push the locking screw through the hole in the centre
front of the inset stove (see photo below). Please note
that this bar may need to be reduced in length if you
are also using a flue liner. Put your hand with the
clamping bar inside the stove and out through the
flue outlet at the top of the stove. Screw the locking
screw into the clamping bar. Position the locking bar
so that it grips against the top of the inside of the
fireplace lintel and turn the screw to tighten, this will
pull the stove tight against the fireplace. Replace
baffle, grate, side and back bricks.
Remove fire grate to
access base fixing hole
Clamp Fixing:
Bar and pre-drilled hole
The clamp grip is attached to the clamp bolt
from inside the stove and then located to lock
against the lintel or other appropriate fixing
point when it is tightened

3 Front fixing
There are also two additional pre-drilled fixing holes
on either side of the stove fire chamber opening that
can be used to attach the stove to the fireplace (see
below).
Carefully position the stove within the fireplace
opening and mark the two holes on to the fireplace
front. Remove the stove and carefully drill the holes
using the appropriate drill bit and insert the screw
plugs. Re-position the stove and insert and tighten
both screws.
Remember, if you are fitting a liner then the liner,
attached to the spigot, should already be dropped and
positioned inside the chimney before the stove is fixed
in place.
Creating an air-tight seal
You must ensure a good seal between the back of the
stove and the face of the fireplace. This is especially
important if you are not using a liner since any air
leaks here could impair the performance of the stove
and also render it unsafe. Fire rope has already been
attached at the back of the stove (allow for this in the
base fixing method). Uneven surfaces such as stone
may need additional sealing. Front fixing and clamp
methods will increase the security of this seal by
drawing the stove tight against the fireplace face and
these are therefore the preferred fixing methods when
a liner is not used.
Front fixing: Use the two
pre-drilled fixing holes on either side
of the fire chamber frame
Fire rope seal: Rough surfaces
such as stone may require
additional sealing
COMMISSIONING
1 Confirm that all internal parts of the stove are
correctly fitted, including the baffle plate
2 Confirm that the door closes correctly and that the
latch mechanism and door seals work to make an
air-tight seal
3 Warm the chimney and carry out a final smoke
draw test
4 Light the stove with a gentle fire, allowing the stove
to increase to an operational temperature level and
check that no combustion products are entering the
room
5 Ensure that the Primary and Secondary air controls
are fully operational
6 Explain the safe operation of the stove to the user
and the importance of using the correct fuel types
7 Explain the requirements of using an approved
fireguard whenever children, the elderly or the
infirm are likely to be in the vicinity of the stove
8 Make sure that the customer receives this copy
of the Instruction Manual
9 Complete the relevant parts of the Horse Flame
Warranty Card with your Hetas / INFO or competent
persons registration number and contact details
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 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 paintwork
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
installation.
17

18
TROUBLE-SHOOTING
CHIMNEY FIRE
If your stove has been installed correctly and you have
also operated it correctly and regularly carried out the
recommended routine checks then it is unlikely that
you will ever experience a chimney fire, which can be
highly dangerous.
Chimney fires can be detected by an unusual roaring
sound and / or unusual vibrations coming from the
chimney breast or the stove itself. The sound is not to
be confused with the gentle ‘rushing’ sound you may
normally hear when a stove has a well performing
up-draught. You may also see sparks or flames exiting
from the chimney terminal outside.
• Prevention
If you suspect a chimney fire then immediately close
the Primary and Secondary air controls, evacuate the
building and call the Fire Service. Never open the
stove door as this will make the chimney fire worse by
providing additional combustion air. Do not re-enter
the building until you have been advised by the Fire
Service that it is safe.
Do not re-light the stove until the flue system has
been thoroughly inspected by an approved installer or
chimney sweep and any necessary repairs have been
carried out.
• Causes: Inadequate cleaning
Chimney fires occur when soot and creosote have
built up to such a level that they ignite. It is important
therefore that your flue system has as many cleaning
access points as practicable to enable comprehensive
removal of soot, creosote and other debris. This will
also minimise the amount of time it takes for a
qualified sweep to clean the system making the
system safer and its cleaning more cost-effective in
the long run.
• Causes: Continuous low burning
To discourage the potential for such soot and creo-
sote build-ups, long periods of consistent ‘slumber’
or overnight burning should be avoided or that these
should at least be compensated for by regular
burning on full output for short periods (eg 30
minutes per day) to help burn off any likely deposits
before they become problematic.
• Causes: Poor fuel choice As previously mentioned
unseasoned or damp wood or fuel should always be
avoided as these produce excessive soot and creosote.
STOVE, FLUE OR OTHER
COMPONENTS GLOWING RED
• Prevention
The Primary and Secondary air controls should be
immediately closed to let the fire die down to an
acceptable level and to reduce the heat output which
will in turn eliminate the glow from the over-heated
components. Over-firing is dangerous and could
permanently damage or warp your stove and its
components. The effects of over-firing are fairly
obvious to anyone in the stove industry and will
invalidate your Horse Flame Warranty. Check the stove
and the flue system for signs of damage before you
re-use the stove.
• Causes: Over-Firing This is caused by using the
stove at a higher output than recommended for
prolonged periods of time and / or over-filling the
firebox with fuel. The excessive heat in the flue system
produced by over-firing could potentially also lead to a
chimney fire (See ‘Chimney Fire’ above).
SMOKE AND FUMES ESCAPING
INTO THE ROOM
When properly installed and operated your stove
should not normally emit fumes or smoke into the
room. 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, but these should
eventually pass as the paint cures. Occasional minor
smoke escape may also occur during the refuelling
process. However, persistent smoke or fumes could be
dangerous and in this situation you should take
immediate avoiding action.
• Prevention
Open doors and windows to ventilate the room and
let the fire go out to allow the stove to cool. Never
pour water onto the fire as this could cause the cast
iron components to break.
Most importantly, never re-light the stove until the
problem has been identified and solved. If in doubt, in
the first instance always seek the expert advice of your
approved installer, or authorised Horse Flame dealer.
There are a number of factors, either alone or
combined, which could cause such problems:
• Causes: A blockage When safe to do so, examine
the flue-way above the baffle plate as well as the
chimney system via any inspection hatches and clear
any soot blockages. Excessive deposits could also
indicate that the chimney or flue itself also needs
cleaning.
• Causes: Inadequate supply of combustion air
Check that any permanent air vent fitted to supply the
extra combustion air required for the stove has not
been accidentally blocked. Remember there should
never be an extractor fan in the same room as a
stove, even in a large open plan area. A simple way of
checking whether or not the stove is receiving enough
combustion air is to open a window in the same room
as the stove whilst the stove is operating. If this
improves the problem then this would certainly
indicate that the stove is being starved of combustion
air and the advice of the original installer should be
sought.

• Causes: Extreme weather conditions High winds
or extremes of temperature can also temporarily
affect the performance of the chimney draught and
consequently its effectiveness in removing smoke and
fumes from the stove’s fire chamber. In the case of
freezing temperatures it is important to build a larger
pre-fire than normal to quickly provide the additional
heat needed to warm the flue system and to
counteract the much lower temperatures at the exit
point of the chimney.
Unusually hot sunny days in the Autumn can
sometimes produce negative pressure which will
affect the up-draught and in these instances you
should open a window or door to the outside to help
re-balance the interior and exterior pressures which
create the up-draught mechanism.
• Causes: High winds If the problem is associated
with high winds and it becomes a regular
occurrence, then you will need to fit a specialist
chimney cowl. These are designed to provide a stable
draught and prevent specific types of problems.
Specifying the right cowl should always be left to an
approved installer.
• Causes: Flue Exit Check, especially at the
beginning of the heating season, that summer tree
growth has not interfered with the free passage of
smoke and flue gases from the chimney top.
OVERHEATING AND EXCESSIVE
FUEL CONSUMPTION
This can be caused by a number of factors.
• Causes: Excessive Chimney Draught This limits
the effectiveness of the air controls so that the fire
burns with very strong bright yellow flames and with
very little difference when the air controls are
operated. In such circumstances an adjustable draught
stabiliser in the flue pipe may need to be fitted to
ensure that the stove will always operate under a
stable draught to allow the stove’s controls to
function correctly. In the interests of safety, because
draught stabilisers limit the exit of flue gases from the
stove, they should only ever be specified, fitted and
subsequently tested by an approved installer.
• Causes: Fuel The fuel itself may be of poor quality.
For example pine and other softwoods used in the
building trade will burn much quicker than a good
hard wood log, such as Oak.
• Causes: Faulty Door Seals The rope seals around
the fire chamber door could have become worn and
may not create the air-tight seal needed for the
Primary and Secondary air controls to function
correctly. When the stove is cold, you can easily check
this seal by placing strips of paper at various points
between the door and chamber and checking that
when the door is closed it grips this paper. Any paper
which can be removed easily would indicate
a weakness of the door seal in that particular spot, in
which case a complete new rope seal should be
fitted.
STOVE NOT PROVIDING ENOUGH HEAT
This problem is also usually indicated by dull orange
lifeless flames and wood that remains black when
burning instead of light grey.
• Causes: Poor fuel Poor heat output is more than
likely caused by poor fuel, such as ‘green’ or
unseasoned wood or even wet wood. We cannot
over-estimate how critical it is to use fully seasoned
dry wood. The easiest way to check whether your
wood is fully seasoned is to invest in a moisture meter
specifically designed for testing wood fuel. These are
relatively inexpensive and can be purchased from your
stove dealer. When you bear in mind that seasoned
wood with a moisture content of less than 20% will
give you approximately 50% more heat than
unseasoned wood, a moisture meter is modest invest-
ment which will more than pay for itself.
Wet or unseasoned wood introduces unwanted
moisture into the fire chamber, reducing the stove’s
operating temperature and thus the effectiveness of
the air wash system. In addition it will cause
problems of increased soot and harmful creosote
deposits within the flue system.
Softwoods such as Pine produce significantly less heat
output than hardwoods.
• Causes: Air controls Ensure that you fully
understand the difference that using the Primary and
Secondary air controls make to the performance of
the stove and the best way to burn your type of fuel.
• Causes: Inadequate Combustion Air A stove
starved of combustion air, even when the Primary and
Secondary air controls are in the fully open position,
will provide limited heat output. Check that any
permanent air vent fitted to supply the extra
combustion air required for the stove has not been
accidentally blocked. Remember there should never
be an extractor fan in the same room as a stove, even
in a large open plan area.
A simple way of confirming whether or not the stove
is receiving enough combustion air is to open a
window in the same room as the stove. If this im-
proves the problem then this would certainly indicate
that the stove is being starved of combustion air and
the advice of the original installer should be sought.
• Causes: Blockages When safe to do so, examine
the flue-way above the baffle plate as well as the flue
pipe and chimney system via the any inspection
hatch and clear any soot blockages. Excessive deposits
could also indicate that the chimney or flue itself also
needs cleaning.
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20
GLASS STAINING OR BLACKENING
Glass can be cleaned easily if it is undertaken regularly
and the deposits are not allowed to build up. A
proprietary stove glass spray or gel is strongly
recommended.
• Causes: Air Controls Ensure that you fully
understand how the Airwash system works and that
you have determined, through some trial and error
that you have the correct balance between Primary
and Secondary air that your stove needs. Generally,
try to use more Secondary air as this air flows down
and over the glass to help burn and wash away any
particulates that have accumulated there.
• Causes: Poor fuel Burning damp or unseasoned
wood will cause the glass to stain as the moisture
from the fuel considerably reduces the fire chamber
temperature reducing the effectiveness of the
Airwash system. ‘Green’ wood will also encourage
sticky deposits on the glass which will prove difficult
for the impaired Airwash system to remove.
• Causes: Continuous low burning Continuously
burning your stove with a very low flame, such as
slow overnight burning will also cause this problem
because the Airwash does not get hot enough and
some blackening of the glass should be considered a
‘trade-off’. In this instance, if you’re sure that the fuel
is seasoned and dry, then burning the stove at very
high temperature for a short period after a long slow
burn will usually burn off any sooty deposits. Glass
can be cleaned easily if it is undertaken regularly and
the deposits are not allowed to build up. A proprietary
stove glass spray or gel is strongly recommended.
ROUTINE CHECKS
During routine checks if you notice anything wrong
with your stove then it should be rectified
immediately. Never use a stove that you know is not
fully functioning – this includes flue components.
• Check your flue system at least once a month using
one of the recommended inspection hatches in the
flue pipe. After a few checks you will notice a
pattern of soot build-up to enable you to determine
the inspection and cleaning period best suited to your
stove’s operation.
• Check and clear the stove’s baffle plate and flue
way at least once a month. Remove the firebricks so
that the baffle plate can be slid forward and dropped
down.
• Make sure the door maintains a good tight fit and
visually inspect the door rope seals for fraying or other
signs of wear. Test the seal if you suspect that it is no
longer air-tight.
• Check that the glass is not chipped or cracked and
that the glass sealing tape is still in good condition.
Replace if necessary.
STANDING DOWN
There will be some point in the year when you will not
need to use your stove for a considerable time and
taking care to clean it thoroughly then will save you
much time later. This is also a good time to get your
chimney swept too as this will prevent any soot build
up from falling inside the stove or ‘caking’ and
blocking the flue way or flue system.
• Remove and clean any deposits from the top of the
baffle plate and check for wear.
• Remove any debris and deposits from the inside of
the stove particularly at the entrance to the flue way.
• Empty the ash pan and thoroughly clean out the ash
pan chamber.
• Check all rope seals and replace damaged ropes that
do not provide a good seal.
• Check the fire cement bonds around the liner joint
and outer spigot plate. Remove any loose cement and
re-seal.
• Check the firebricks and replace any that have
become thin or worn.
• Check the grate for signs of wear. Excessive wear,
such as grate bars or log retaining bars which are bent
or warped, could be an indication of over-firing or
using inappropriate fuels such as petroleum coke.
Order genuine replacement components from your
authorised Horse Flame dealer.
ROUTINE MAINTENANCE
• Baffle Plate and Flue Way During the heating
season check the flue way and baffle plate at least
once a month to start with and remove any soot
deposits. Should these be excessive then have your
chimney and flue cleaned. At the same time review
your choice of fuel and the way that you operate the
stove. See page 6 ‘Removing The Baffle Plate’
Regular long periods of slow or overnight burning can
create excessive soot because the stove is not
operating at the temperature required to burn off
most of the sooty. Damp or unseasoned wood will
also have similar effect. To find a local registered
sweep visit www.guildofmasterchimneysweeps.co.uk
or www.chimneyworks.co.uk.
• Chimney Cleaning The Precision Inset can be
swept through the stove by simply removing the
baffle plate. The baffle plate can be slid forward and
dropped down. See page 6 ‘Removing The Baffle
Plate’
Sweep your chimney before installation and then at
the end of each heating season when you stand down
your stove. Burning seasoned dry wood means that
you will probably need to sweep every three months.
The amount of soot deposits removed each time is a
good indication of how often you should sweep and