FORMA WOOD CLOSED FIREPLACE
Chapter 2
USE AND MAINTENANCE MANUAL
page
11
Theoretical recommendations for installation
Technical dept. - All rights reserved by MCZ Group S.p.A. - Reproduction prohibited
2.6.
CHIMNEY
If the chimney is underestimated it can often prevent the "chimney
system" from operating correctly.
The draught of the flue pipe also depends on its chimney.
It is therefore vital that, if the chimney has been hand-crafted, the
development of the four relief sections correspond
to more than
twice the internal cross-section of the flue pipe.
As the chimney must always be higher than the ridge of the
roof it will be exposed to wind in all directions. Therefore, an
industrial-type chimney is recommended.
The chimney must:
Have an inner section equal to that of the flue.
Have a working outlet section of at least double that of the
inner section of the flue pipe.
Be built in such a way as to prevent rain, snow and any
foreign bodies from penetrating the flue pipe.
Be positioned so as to ensure adequate dispersion of smoke
and, in all cases, outside the reflux area in which back-
pressures are likely to form.
In the case of paired flue pipes, the solid
combustibility or upper storey chimney shall be at
least 50 cm higher than the others in order to avoid
the transfer of pressure from one paired pipe to the
other.
There must be no obstacles present within a range of
10 linear metres of the chimney. This includes walls,
pitches and trees. If obstacles are present raise the
chimney at least 1 metre above the obstacle and, if
there are other chimneys nearby, space them at least
2 metres apart. In all cases the chimney must
protrude from the ridge of the roof by at least 1 linear
metre.
Industrial chimney
with prefabricated
stacked elements,
allows excellent
smoke discharge.
Traditional hand-
crafted chimney.
The correct outlet
cross-section should
be at least twice the
internal cross-
section of the flue
pipe, ideally 2.5
times its size.
Steel flue pipe
chimney with internal
smoke-deflector cone.
1
m
t
0,
5
m
t
