3
damper is fitted in the flue gas pipe,
there must always be at least 20 cm2
of free passage, even when the dam-
per is in its “closed” position. If local
regulations permit, two contained fire-
places can be connected to the same
chimney. However, you must abide by
local regulations regarding the distan-
ce between the two connections.
Wood-burning stoves must never
be connected to chimneys that are
also linked to a gasfired heater. An
efficient stove makes high demand on
chimney properties – so always have
your local chimney sweep evaluate
your chimney.
Connection to a brick chim-
ney
Brick a thimble into the chimney and
seat the flue gas pipe in this. The
thimble and flue gas pipe must not
penetrate the chimney opening itself,
but must be flush with the inside of
the chimney duct. Joins between
brickwork, the thimble and flue gas
pipe must be sealed with fireproof
material and/or beading
Connection to a steel chimney
When fitting a connection from a top-
output stove directly to a steel chim-
ney, we recommend fitting the chim-
ney tube inside the flue gas spigot so
that any soot and condensation drops
into the stove itself rather than col-
lecting on the exterior surface of the
stove. Changing smoke outlet from
top-mounted to rear-mounted (see fig.
14+15 on page 14).
For connections to chimneys that are
run through ceilings, all national and
local regulations regarding distance to
flammable material must be followed.
It is important that the chimney is
fitted with roof support so that the top
panel of the stove is not required to
bear the entire weight of the chimney
(excessive weight may cause damage
on or noise from the stove).
Draft conditions
Poor draft may result in smoke being
emitted from the stove when the door
is opened. The minimum chimney
draft to ensure satisfactory combu-
stion in stoves of this kind is 13 PA.
However, there will still be a risk of
smoke emission if the firing door is
opened during powerful firing. The flue
gas temperature at nominal output is
274°C when expelled to an exterior
temperature of 20°C. The flue gas
mass flow is 5.1 g/sec. The chimney
draft is generated by the difference
between the high temperature of the
chimney and the low temperature of
the fresh air. The length and insulation
of the chimney, wind and weather
conditions also have an effect on the
ability of the chimney to generate ap-
propriate under-pressure.
If the stove has not been used in a
while, check that the chimney and
stove are not blocked with soot, bird
nests, etc., before using it.
Reduced draft can occur
when:
• The difference in temperature
is too small – due to insufficient
chimney insulation, for example.
• The outdoor temperature is too
high – in summer, for example.
• No wind is blowing.
• The chimney is too low and shel-
tered.
• The chimney contains false air.
• The chimney and flue gas pipe are
blocked.
• The house is too airtight (i.e. when
there is an insufficient supply of
fresh air).
• Poor smoke extraction (poor draft
conditions) due to a cold chimney
or bad weather conditions can be
compensated for by increasing
the airflow into the stove.
