Alpha Multi Fuel Stoves AL357i-B User manual

Model AL357i-B Alpha Inset Boiler
Multi Fuel and Wood Burning Inset Boiler Stove
Instruction Manual
www.alphastoves.com
- -
Published September 2012
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 effi cient operation.
You will need to refer to the serial number of your
stove should you ever need to make a claim under
the Alpha Warranty. You will fi nd the serial number,
beginning with AL, on the CE plate at the rear 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.
Remember to keep your receipt as proof of purchase.
Ref: AL357i-B / UK-NI-ROI / V1.01-09-12
ALPHA
Collection
The

CONTENTS
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General Dimensions
General Specifications
Replacement Consumables
Standard Features
Important Safety Advice
Boiler Stoves: Specific Safety Issues
Health and Safety
Building Control and Hetas
Installation Regulations
UK Smoke Control Areas
Buildings Insurance
Packing List
Assembling the Stove
Removing the Baffle Plate
Recommended Fuels
Prohibited Fuels
Understanding Fuel Types
Controlling The Combustion Air
Burning Wood Logs
Lighting a Wood Fire
Burning Mineral Fuels
Overnight Burning
Removing Ash
Installation Check-list
Appliance installation Guidelines
System installation Guidelines
Basic System Essentials
Basic System Diagram
Fitting Instructions
Commissioning
Important: First Fires
Condensation
System Balance
Trouble-shooting
Routine Checks
Routine Maintenance
Standing Down
The Alpha Warranty
Alpha Spare Parts
Annual Service
Service Record
System Notes and Settings
3
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
Alpha Inset stove. However, the principles illustrated
here remain the same.
Hi-Flame Fireplace (UK) Limited
INTRODUCTION
Thank-you for purchasing the Alpha Inset
Boiler 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 inset boiler
stove however, in the interests of safety,
please read this booklet which contains
important safety advice as well as
instructions which will help you make the
most of your new boiler 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.
IMPORTANT
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 Alpha
Inset Boiler can only be fuelled with approved
smokeless fuels – it will be illegal to burn wood
in it.

GENERAL DIMENSIONS
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STANDARD FEATURES
1 Primary Air Control Air which enters under the
grate for multi fuel burning and to assist a wood log
fire to get 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
4 Thermostat Control This adjusts the temperature
of the water leaving the boiler from low to high by
controlling part of the combustion air supply to the
fire chamber
4 System Ports There are four 1” BSP water ports –
two on either side of the firebox
5
GENERAL SPECIFICATION
Model Name Alpha Inset Boiler
Model Number AL357i-B
Dimensions (mm): Facia H605 W490 D 95
Dimensions (mm): Firebox External H515 W380 D175
Net Weight 109 kg
PERFORMANCE
From Kiwa GasTec BS EN13229: 2001 Test Aug 2012
WOOD
Intermittent Burning – 1.0 hour refuel period
Nominal Heat Output To Room 4.8 kW
To Water 7.5 kW
TOTAL 12.3 kW
Efficiency (net) 80.2%
Mean CO Emission (at 13%) 0.52%
Mean Flue Gas Temperature 296ºC
Flue Gas Mass Flow 7.0 g/s
MINERAL FUELS (Ancit)
Continuous Burning – 2.0 hour refuel period
Nominal Heat Output To Room 3.7 kW
To Water 8.9 kW
TOTAL 12.6 kW
Efficiency (net) 75.8%
Mean CO Emission (at 13%) 0.47%
Mean Flue Gas Temperature 333ºC
Flue Gas Mass Flow 7.6 g/s
MINIMUM DISTANCES
Minimum Distance from Combustible Materials
Top (shelf) 200 mm
Sides 100 mm
FLUE
Flue configuration top only
Flue outlet diameter 150 mm (6”)
Minimum flue height from top of Inset 4,500 mm (15’)
BOILER
Factory pressure tested to 3.5 Bar maximum
Water capacity 10kg / 10L (2.2 Gal)
Maximum operating Pressure <1.5 Bar
Pipework ports Four x 1” BSP
RECOMMENDED FUELS
Wood Logs: Moisture content <20%
Maximum Wood Fuel Load 3.6 kg (approx 8 lb)
Maximum Log Length 275 mm (11”)
Or Approved Smokeless Fuels (www.solidfuel.co.uk)
Maximum Mineral Fuel Load 3.7 kg (approx 8 lb 2 oz)
REPLACEMENT CONSUMABLES
Heat Resistant Glass 285 x 325 x 4 mm
Door Rope Seal 10 mm dia x app 1700 mm (5’8”) long
Ash Pit Rope Seal 10 mm dia x 370 mm (15”) long
NB There are no firebricks on the Alpha inset Boiler
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6
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 Kiwa 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.
BOILER STOVE SYSTEMS –
SPECIFIC SAFETY ISSUES
• This stove requires a dedicated non-closable air
vent of the appropriate size for its maximum heat
output and this should be located in the same room
as the stove. An adequate supply of combustion air
is essential for the safe operation of this stove – see
page 5 for maximum outputs.
• The system should not rely solely on gravity fed
circulation but must also incorporate a circulation
pump.
• This stove should not be connected directly to a
sealed or pressurised system without including a
safety ‘buffer’ between the systems such as a thermal
store, heat exchanger or specialist link-up component.
This will also help neutralise any pipe size difference
between the two systems which could adversely affect
performance.
•The cold feed and open vent flows must not be
fitted with any manual or automatic valve. The system
flow must not be able to be ‘closed off’ so that there
is always a clear flow route from the stove to the
system’s open vent
• In the event of a power cut or circulation pump
failure your stove will continue to produce hot
water which could be potentially dangerous. Your
system design should therefore provide for the safe
dissipation of excess hot water through a heat loss or
heat leak radiator.
• Motorised valves must revert to the open position in
the event of a power failure. This will allow heat to be
safely dissipated through the system’s natural gravity
circulation process.
• Although it is common practice for heat leak
radiators to be located in an upstairs bathroom it is
worth noting that on some boiler stove systems the
heat leak radiator can get very hot and therefore we
recommend installing a low surface temperature type
radiator and / or locating it where young children or
the infirm won’t accidentally come into contact with it
• The heat output to water from this boiler stove must
not be significantly greater than any potential usage.
The system’s heat release feature, especially if linked,
must be sufficient to prevent the system from over-
heating.
• The system design must incorporate a drain point,
preferably near the boiler stove, and be sufficient
to empty the system of any residue water during
maintenance or removal.
• All electrical connections, for example to system
valves, the circulating pump and the link-up
component must comply with current Building
Regulations. Ensure that the pipework is correctly
earthed. See page 7 for relevant regulations.
• The mains water connection to the system must

comply with local water authority regulations in order
to safeguard water quality and public health – see
page 7.
• The hot water cylinder thermostat should be set at
60ºC (and tested) to prevent scalding – see page 20.
ASBESTOS
This stove does not contain Asbestos. However, check
that there is no possibility of disturbing any asbestos
based materials during its installation. You may
intend removing an older appliance prior to installing
your new stove, and you should be aware that the
old appliance or installation could incorporate heat
protective asbestos sheet – if in doubt seek guidance
at www.hse.gov.uk/asbestos – do not underestimate
the potential dangers of Asbestos.
FIRE CEMENT
Prolonged contact with fire cement and skin should
be avoided. Protective gloves and glasses should be
worn when applying fire cement. Care should also be
taken to avoid contact between the stove’s surfaces
and fire cement as this will damage the paintwork.
Any excess fire cement should be quickly removed
before it hardens. Always follow the manufacturer’s
instructions.
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. When using fire cement always follow the
manufacturer’s instructions.
BUILDING CONTROL AND HETAS
In the United Kingdom most installations of solid fuel
and wood burning appliances and systems are subject
to the requirements of Building Regulations. These
regulations must be observed and such installations
need to be notified to the relevant Local Authority
Building Control department by law.
Hetas (www.hetas.co.uk) is the official body
recognised by the Government to approve solid fuel
domestic heating appliances and the registration of
competent installers.
HETAS registered installers in England and Wales
can self-certificate their work thus avoiding the
need for costly and time consuming Building
Notice applications to the local Building Control
department. They will provide you with a certificate
of compliance upon completion of the installation
and send a copy to Hetas for onward notification to
your local authority. The certificate of compliance is
an important record demonstrating that the work was
carried out legally and in accordance with the relevant
Building Regulations and by a trained and competent
installer of a registered business.
Should you ever come to sell your property, the
information about work carried out under Building
Regulations is required and used by solicitors on their
enquiry forms. Failure to demonstrate compliant work
could adversely affect the sale of your property.
More information on the Building Regulations
process can be found on the Communities and Local
Government website www.labc.uk.com
INSTALLATION REGULATIONS
You must ensure that your boiler stove is installed by
a recognised competent person who is appropriately
qualified in the installation of boiler 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
7

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.
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 Alpha
Inset stove if it is located in a building within a Smoke
Control Area. In such a case you must only use an
Approved 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 which have been written to help you
minimise the amount of smoke produced from your
stove.
See page 11 for recommended fuels for your Alpha
Inset Boiler stove.
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.
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 Flue Spigot and 2 Securing Bolts
E Flue Spigot
F Ash Lip
G Screw and Anchor for base fixing
H Fire Grate and integral Log Bar (in place)
J Baffle Plate (Located inside roof of fire chamber)
Equipment
K 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
8

ASSEMBLING THE STOVE
Your new inset boiler 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
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
Alpha 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 the stove from its recyclable
packaging. You must 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 Packing List on page 8
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 to warm
the water.
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 10
• Flue spigot plate To maximise efficiency and safety
the AL357i-B Inset Boiler stove has been designed to
work best in conjunction with a 150mm (6”) flexible
flue liner connected to the purpose-designed spigot
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 strongly
recommend that a liner is always used. If you are
proposing to burn mineral fuels then 904L grade liner
is recommended as this will provide greater resistance
to the combined corrosive affects of moisture and the
acid content of certain mineral fuels.
Should it not be possible to fit a liner then in the
interests of safety another means of being able to
clean the flue system and top of the stove, for
example a soot box, should be created in the chimney.
The householder should ensure that the chimney is
regularly swept (at least twice a year when burning
wood) and at the same time if possible, the stove
removed so that the top can be thoroughly cleared
of any soot and debris build-up. See page 18 for
instructions on safely sealing the fireplace back plate.
• System ports Each of the four water ports on your
inset boiler has been fitted with a bolt seal. To avoid
the internal threads being contaminated with grit
and other debris please ensure that these are only
removed when the system pipework is ready to be
connected.
• 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. Remember not to lift or position the
stove using the door or handle.
Your inset boiler stove is now ready for installation.
9

10
REMOVING THE BAFFLE PLATE
Regular checking of the baffle plate will ensure that
the stove’s flueway stays clear of soot as well as
ensure 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 familiar-
ise yourself with this procedure before the stove is
installed.
With the Alpha Inset Boiler there are no baffle fixing
brackets, bolts or fire bricks to remove.
Firstly, Protect any decorative finishes such as porous
stonework, tile grout or carpets as there will
To back of stove
3 Carefully remove from the fire chamber
2 Drop down at angle
1 Push upwards and pull forward
inevitably be some sooty debris removed with the
baffle. When the stove and boiler are cold, 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 slightly and dropped down on
one side to clear the fixed retainers ready for inspec-
tion and cleaning.
To replace the baffle, simply reverse the operation –
ensuring that it sits securely along the retaining ledge
at the back of the fire chamber and that there are no
air gaps between the retainer sand the baffle.
Remember, only attempt to remove the baffle when
you are sure that the inside of the stove is cold.

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 Alpha for use in the
AL357i-B Inset Boiler 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 – a matter of weeks sometimes, 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
In the event of a problem with your stove – always
check your choice of fuel first!
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,
potentially corrosive, 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).
Should you prefer to burn peat then we would
strongly recommend using 904L grade flexible liner to
line your chimney.
• 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 bituminous 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 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.
11

• 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
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.
12
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 Alpha Inset Boiler stove has three simple to use
air controls:
1 Primary Air Control This is the large control knob
in the centre at the base of the stove front. Primary
Air is required when burning mineral fuels (and to
quickly aid the supply of air during the initial
combustion of wood). Using the tool provided, 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 usually needed when
burning mineral fuels (unless it is to maximise the air
supply to aid the initial combustion).
3 Thermostat Control Zero is closed and 8 fully
open. This adjusts the temperature of the water
leaving the boiler from low when closed off (approx
50Cº) to high (approx 90Cº) by controlling part of the
combustion air supply to the fire chamber.
The effectiveness of adjustment will involve the
interaction of the Primary and Secondary Air supply
The Primary Air Control
The Secondary Air Control

13
and other factors such as the fuel type, the system
set-up and the pump flow speed. Finding the right
setting(s) will be a matter of trial and error as well as
personal preference. For example the Thermostat
Control, can sometimes be used for simultaneous
control of both the water temperature and the burn
rate of a mineral fuel load by shutting of both the
Secondary Air and the Primary Air.
It is worth noting that this control does not ‘turn off’
the hot water production completely and that your
system design must therefore include a means to
dissipate any surplus heat. See page 20
BURNING WOOD LOGS
Important: Try not to exceed the recommended
log length. This size allows approximately 25mm
(1”) of space at either end of the log to prevent
cold water spots.
Remember, these instructions are an initial guideline
to help you get started. As you begin to gain
experience of your stove and choice of fuel(s), as well
as your flue system, you will be able to adjust these
procedures and control settings to your personal
preference.
As previously stated wood burns best on a bed of its
own embers which also forms a barrier to reflect heat
and protect 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 – never let
the ash pan get over-filled. Once you have lived with
your stove for a while you’ll soon get to know how
often you should do this.
Ensure that there is a gap of approximately 25mm
(1”) between both ends of the logs and the boiler
sides. Log ends placed against the boiler sides restrict
combustion and can create unwanted cold spots in
both the log and the water. As the end grain of the
wood produces more of the remaining moisture and
gases, whenever possible point the log ends away
from the glass to help keep the glass clean.
Fuel Load Ideally the logs should be approximately
275mm (11”) long. A typical fuel load should weigh
2.5 kg (5lb 8oz) with a maximum load of 3.6kg (8lb).
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
temperature, 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.
Thermostat Control
Avoid abutting the logs against the
boiler sides which creates cold water spots

14
1 The Lighting Phase
For best results:
Primary Air (bottom control) – fully open
Secondary Air (top control) – fully open
Thermostat Control – fully open (8)
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
Secondary Air settings, as well as the Thermostat
Control, 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
Thermostat Control – fully open (8)
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.
3 The Main Firing Phase
For best results: After 17 or 18 minutes...
Secondary Air (top control) – remains open
Primary Air (bottom control) – remains closed
Thermostat Control – remains fully open (8)
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 1.5kg 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 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
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.
If you are lighting the stove to firstly provide hot water
and heat into your central heating, rather than heat
into the room, you should not need to adjust the
Secondary Air or Thermostat Control until you are
satisfied that both of these have been achieved. This
could take as long as two hours and will probably
require at least one full refuel.
4 Refuelling
For best results: Just before you refuel...
Primary Air (bottom control) – fully open
Secondary Air (top control) – fully open
Thermostat Control – fully open (8)
After loading and when new fuel is burning well...
Primary Air – close completely
Secondary Air– adjust to suit
Thermostat Control – adjust to suit (0 – 8)

15
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, as well as the Thermostat Control, so that
there is a good strong fire and the embers are glowing
red to 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
additional air so make sure the Secondary Air and the
Thermostat Control are back in the fully open position
after refuelling. Do not adjust the Secondary Air or
Thermostat Control until the fire is burning well and
you can see bright yellow vigorous flames.
Once the fire is established, usually after about five
minutes, close the Primary Air and adjust the flame
pattern again to your requirements with the
Secondary Air and Thermostat Controls.
If the new wood fuel is slow to catch alight, even with
the Primary, Secondary and Thermostat Air fully open
then try opening the stove door slightly to 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.
5 Controlling the boiler temperature
This will be very much a matter of trial and error
using the guidelines above. When the stove has been
running at operating temperature for a number of
hours the Thermostat Control, can be used for
simultaneous control of both the water temperature
and the burn rate of wood fuel load (and therefore
the heat into the room). To do this, ensure the Primary
Air is fully closed, adjust the Secondary Air so that
some combustion air is still provided to ensure the
Airwash will continue to work. Then simply control
the flame pattern and burn rate with the Thermostat
Control. if the glass begins to soot up provide more
Secondary Air.
Some simple wood burning tips
1 Boiler stoves operate at a much lower temperature
than non-boiler stoves and consequently the potential
to create soot or creosote build-up in the flue system
is also much greater, especially when operating the
stove in ‘slumber’ mode during overnight burning.
We therefore recommend burning your Alpha Inset
Boiler on high output for at least 30 minutes each day
to help burn off any potential soot or creosote build-
up – but be careful not to over-fire the stove.
2 Small regular loads when refuelling will produce a
more efficient and cleaner burning performance.
3 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.
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 established.
5 Bright vibrant flames and a clean fire chamber
indicates that your stove is operating well.
BURNING MINERAL FUELS
These instructions are an initial guideline to help you
get started. As you begin to gain experience of your
stove and choice of fuel(s), as well as your flue system,
you will be able to adjust these procedures and
control settings to your personal preference.
Mineral fuels require much more combustion air
from below the fuel load than wood. This means
that Primary Air is generally needed throughout the
initial burning phases. The Primary Air control should
always 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 source
– therefore, always ensure that the firegrate is clear.
The maximum recommended mineral fuel load for
this stove is 3.7kg (8lb 2oz).
1 The Lighting Phase
For best results:
Primary Air (bottom control) – fully open
Secondary Air (top control) – fully open
Thermostat Control – fully open (8)
Door – slightly ajar (optional)
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. On very cold days increase
the amount of kindling used to ensure a good up-
draught in your flue system is quickly established.
2 The First Refuel Phase
For best results: After 10 -15 minutes...
Primary Air (bottom control) – fully open
Secondary Air (top control) – adjust to suit
Thermostat Control – fully open (8)
Door – closed
Once the mineral fuel is burning well then add some

additional fuel (but not too much so that it ‘kills’
the mineral fuel that’s already alight), until there is a
good bed of burning fuel. Avoid stacking too much
fuel against the back and sides of the boiler as this
could potentially overheat the stove’s components and
cause permanent damage. Ideally, when fully burning
the fuel load should look like a shallow dome.
When burning good quality mineral fuels Secondary
Air (Airwash) should not be needed to keep the glass
clean, therefore the Secondary Air can be reduced or
shut off completely. The Primary Air control should
then be used to adjust the flame pattern in the early
stages. You may find that a combination of subtle
adjustments to both air controls may best suit your
individual requirements. Leave the Thermostat Control
fully open until the heating and hot water system is at
the desired temperature – this is usually after a couple
of hours and depends on the system requirements.
3 Refuelling
For best results: Just before you refuel...
Primary Air (bottom control) – fully open
Secondary Air (top control) – fully open
Thermostat Control – fully open (8)
After loading and when new fuel is burning well...
Primary Air – adjusted to suit
Secondary Air– fully close or adjust to suit
Thermostat Control – adjust to suit (0 – 8)
When refuelling it is better to use smaller fuel loads
more often which will provide you with a cleaner,
more efficient burn.
Immediately after refuelling, open the Primary Air 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 new 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.
4 Controlling the boiler temperature
As previously stated this will be very much a matter of
trial and error using the guidelines above. When the
stove has been running at operating temperature for a
number of hours the Thermostat Control, can be used
for simultaneous control of both the water
temperature and the burn rate of the mineral fuel
load (and therefore the heat into the room). To do
this, ensure the Primary and Secondary Air is fully
closed. Then simply control the flame pattern and
burn rate with the Thermostat Control. However, you
may still need to undertake some subtle adjustments
to both the Primary and Secondary Air supply to
achieve the correct balance of combustion air for your
stove and flue system draught.
OVERNIGHT BURNING
The Alpha Inset Boiler 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. If burning wood, then limit the
Secondary Air supply and ensure the Primary Air
supply is closed. Adjust both the Thermostat
Control and Secondary Air to achieve a slower burn
rate. If the glass begins to soot up then add some
more Secondary Air (Airwash).
Do not ‘starve’ the fuel of combustion air as this could
create a very inefficient smoky burn and cause heavy
soot and creosote build-ups in the flueway and fuel
system. 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
adjust the Primary and Thermostat Air supply to
achieve a slower burn rate.
When you return to your stove, check the ash pan
does not need emptying, then fully open all three air
supply controls. If the firebed shows that it still has
sufficient burning embers then simply add a small fuel
load as if lighting the fire from the start (see above)
and add more fuel until you have a good fire.
If you have been burning mineral fuels you will
probably need to riddle the firegrate to re-establish
the Primary Air flow. Do not add a full fuel load until
the firebed is hot and any initial small fuel load has
been allowed to fully ignite. A large ‘cold’ fuel load
could easily starve the embers of combustion air and
put out the fire.
Always operate fully burning for approximately 30
minutes to burn off any overnight soot deposits
before you revert to your preferred operating levels.
During overnight burning the stove glass may blacken
but if dry wood fuel has been used and a hot fire is
re-established then these deposits should quickly burn
off. However, if there are no burning embers and you
need to start the fire again, simply wipe any deposits
from the glass using kitchen roll or newspaper. Do not
use a damp cloth or proprietary cleaning fluids unless
you are sure that the stove glass at least is at room
temperature.
16

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.
Wood ash can be composted or used in the garden.
The forked end of the tool is inserted underneath the ash pan grip
as shown above to create the ash pan handle.
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, nor is it intended, 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
conforms 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 the 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 permanently
open dedicated air supply within the room which
must conform to applicable building regulations. The
AL357i-B Alpha Inset Boiler stove has been officially
rated at a maximum output of 12.6kW and therefore
the installation must incorporate an appropriately
sized air vent.
• 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
Alpha Inset is 4.5 metres (15’) from the hearth to the
top of the chimney terminal.
17

18
• 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 AL357i-B Alpha Inset are as follows:
Top (eg mantel shelf) 200 mm
Sides (eg fire surround) 100 mm
APPLIANCE INSTALLATION:
GENERAL GUIDELINES
Please refer specifically to current building regulations
which apply to your country or region. Adopt
whichever provides the highest / safest margin.
Asbestos
This stove does not contain Asbestos. However, check
that there is no possibility of disturbing any asbestos-
based materials during its installation. You may
intend removing an older appliance prior to installing
your new stove, and you should be aware that the
old appliance or installation could incorporate heat
protective asbestos sheet or other asbestos-based
materials – if in doubt seek guidance at www.hse.
gov.uk/asbestos – do not underestimate the potential
health hazards of handling Asbestos.
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
thickness 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) and boiler (with water add 10kg) 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
combustible 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.
Inset Stove Fireplace Opening
Your Alpha Inset stove has been designed to fit
relatively easily within a 16” x 22” (400mm x 550mm)
standard builders’ fire opening.
• Redundant back boilers or ‘Baxi’ type ash pits and
air intakes ideally should be removed, filled and
levelled.
• Existing fireplaces and hearths must be made of
non-combustible materials as well as be suitable for
use with a solid fuel stove. For example the hearth
and backplate ideally should be ‘slabbed’ with
concrete and any decorative surface finishes, such as
marble, should be ‘tiled’ to allow for heat expansion.
• Ensure that any existing fire surround or fireplace
back plate you propose to re-use or leave in position is
secure and that any air gaps between it and the back
wall are sealed, particularly around the actual fireplace
opening and the backplate interface. It is important
for safety reasons that this seal is air tight.

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• Where possible once the stove position has been
settled upon any significant gaps along the side and
back of the inset stove should be filled with a suitable
inert material such as rockwool. A vermiculite and
cement mix (6 parts vermiculite to 1 part cement)
can be used for filling large spaces – but under no
circumstances should it be packed against the stove
sides or pipework thus limiting the potential for the
stove to be accessed or easily removed at some later
point.
Flue Draught
The Alpha Inset has been tested with a flue
draught pressure of 12pa and therefore to ensure
performance which is line with the test results on
page 3 the ideal flue draught pressure should be
approximately 12Pa.
The Chimney, Flue and Flexible Liners
Other flued appliances must not share or be
connected to the same flue system or chimney as this
stove.
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 stove 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 po-
tential 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 boiler 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. If you intend
to predominantly burn mineral fuels then 904L grade
liner will provide greater resistance to any acidic
condensates produced by burning certain mineral
fuels.
Alpha 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
with vermiculite will deliver much needed insulation
to keep flue gases as hot as possible (particularly
important for boiler stoves) 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.

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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.
Important: If you are not using a chimney liner
you must provide a means of inspecting the flue
system and the top of the stove.
SYSTEM INSTALLATION:
GENERAL GUIDELINES
Central heating systems
A pumped central heating circuit combined with a
gravity hot water circuit is generally the accepted
specification for multi fuel boiler systems which are
not linked to another system. However, achieving
the correct balance between the pumped and gravity
flows in such a system is critical to the efficient
performance of the boiler stove and should be left
to an experienced Hetas wet installer or appropriate
specialist registered on a Competent Persons scheme.
Increasingly new systems are specified as ‘fully
pumped’ to provide improved operational control and
this is a feature that we would recommend for your
system.
Dual fuel linked systems
You may have purchased your new Alpha Inset Boiler
stove with the intention of adding it to an existing
heating system powered by a different fuel type. This
is likely to be to a non-pressurised oil or gas system,
but could also be solar powered, probably in a new
pressurised system.
Linking two such systems requires specialist
knowledge to ensure a fully functioning system which
is efficient, safe and legal. Such systems require the
installer to possess a knowledge and understanding
which will be beyond the provisions and intentions of
these general installation and operating guidelines.
The United Kingdom’s Solid Fuel Association
through their website www.solidfuel.co.uk, provides
informative downloads on various link-up system
solutions.
The most common problem with link up systems is
a failure to understand the existing system which
may have faults which are then exacerbated by the
new link. Our advice when linking this boiler stove
to any system is therefore to consult the appropriate
installation expert who will develop an understanding
of your requirements and provide you with a
thorough survey of any existing system.
There are various Government competent persons
schemes listing installers trained in designing and
installing linked systems:
• Hetas www.hetas.co.uk
• Association of Plumbing & Heating Contractors
(Certification) www.aphc.co.uk
• Building Engineering Services Accreditation
www.besca.org.uk
• NICEIC www.niceic.org.uk
BASIC SYSTEM ESSENTIALS
The basic system diagram on the opposite page
should be used for general guidance purposes only
and is included here to demonstrate basic system
principles. Combined with the at-a-glance list below
this should provide you with a basic understanding of
the essential requirements your system should have.
As each system and its requirements will vary the list
below is by no means meant to be comprehensive.
A good system should adhere to the following:
• Adjustable flow circulating pump
• High and low limit thermostats
• Cold feed pipework must be minimum 22mm dia’
• Open vent pipework must be minimum 22mm dia’
• Overflow pipe must be 22mm dia’ copper
• All pipework must be able to operate at
above 100ºC
• Feed / expansion tank must be galvanised steel
or copper
• Float valve should also be copper
• No automatic or manual valves on cold feed
or open vent pipework
• Heat leak radiator fitted to gravity circuit
• Exposed pipework (eg lofts) must be insulated
to prevent freezing
• Hot water cylinder and thermostat
• System should be capable of being completely
drained
Heat leak radiator
A heat leak radiator with a minimum rating of 10%
of the boiler’s total output to water should be fitted
to the gravity circuit. Heat leak radiators rated at
approximately 2kW (6,800BTU) tend to be the norm
in most systems. Pipes to and from the heat leak
radiator can be reduced to 15mm diameter provided