PART FOR THE INSTALLER
Always respect all norms and standards in the country of installation.
Ensure that the chimney (if it is an existing one) is compatible and suitable for the unit to
be installed. The chimney and/or flue is critical to the correct functioning of the unit –
ensuring the correct delivery of fresh air to the unit for primary combustion and for the
elimination of the combustion fumes.
Most heater/ insert malfunctions are due to a fault with the chimney flue – this point
cannot be emphasized enough….
One should not be content in referring to results obtained with a previous heater – the air intake
requirements may differ.
A good chimney should be made of material that is a low conductor of heat and that does
not cool down too easily.
If the internal volume of a brick chimney, or existing tubing, is too high it may be necessary
to run a new liner in the chimney. Any bends must be gentle and as straight as possible.
Mechanical sweeping of the chimney must be possible – there should be no restrictions or
sharp bends.
If there is any combustible material in the rear wall of the chimney (some types of
insulation) this should be removed across the full width of the chimney and up to the height
of the ceiling. Any beams (exposed or enclosed) in the vicinity should not be exposed to any
temperatures exceeding 50⁰C.
In cases where combustible material has to be removed then the wall should be rebuilt using
materials with good thermal insulation properties – cellulose concrete for example.
If there is a combustible mantle piece (wooden beam) it must be protected on the inside and
underside by incombustible material or by a deflector. There must be no direct physical
contact between the material protecting the mantelpiece and the heater itself.
The flue diameter for correct functioning of the unit is recommended to be 150mm – though
125mm is acceptable.
The flue diameter must never be reduced.
The chimney must originate in the room where the heater is installed.
The flue and chimney must be airtight.
Any flue or conduit used must be resistant to chimney fires and be designed to withstand
temperatures 50⁰C higher than the declared operating temperatures of the heater.
Reducers on the air intakes are not permitted.
The flue must be homogenous.
Flue pipes or tubing used must be suitable for heater installations and be able to resist to
chimney fires. The flue must be able to withstand temperatures 50⁰C higher than the
declared smoke/fume temperature for the unit – whatever the installation method.
The height of the flue should not be less than 5 metres and should exit into “free” air at least
40cm above the crest of the roof or any higher obstacle that may be within 8 metres of the
chimney.
Any changes in the angle of the chimney must be as gentle as possible (a 30⁰ bend is highly
preferable to a 90⁰ bend).
The draw should be between 12 and 15 Pascals during normal (average) operation and when
running on a normal average setting the draw should not drop below 12 Pascals as the
