Flue; Position Of The Chimney Pot - Nordica ITALY Termo - DSA Handbuch

5.

FLUE

Essential requirements for correct appliance operation:
•
the internal section must preferably be circular;
•
the appliance must be thermally insulated and impermeable
and built with suitable materials which are resistant to heat,
combustion products and any condensation;
•
there must be no narrowing and vertical passages with
deviations must not be greater than 45° ;
•
if already used, it must be clean;
•
the technical data from the instruction manual must be
respected;
If the flues are of a square or rectangular section, the internal edges
must be rounded with a radius of not less than 20 mm. For the
rectangular section, the maximum ratio between the sides must be ≤
1.5.
A section which is too small causes a reduction in draught. A minimum
height of 4 m is advisable.
The following are FORBIDDEN and therefore jeopardise the correct
operation of the appliance: asbestos cement, galvanised steel, rough
and porous internal surfaces. Picture 5 shows some example solutions.
The minimum section must be 4 dm
appliances whose pipe dimensions are less than 200mm, or
2
6.25dm (for example 25x25cm) for appliances with a diameter of
more than 200mm.
The draught created by your flue must be sufficient but not
excessive.
A section of the flue which is too large can present a volume which is
too large to heat and therefore cause operating difficulties for the appliance; to avoid this, it is necessary to intubate
the appliance for its entire height. A section which is too small causes a reduction in draught.
The flue must be suitably distanced from flammable or combustible material using suitable insulation or an
air space.
It is FORBIDDEN to pass system piping or air ducts inside the flue. It is also forbidden to create moveable or fixed
openings on the flue itself, for the connection of further different appliances.
IMPORTANT: refer to chapter 16.
5.1.

POSITION OF THE CHIMNEY POT

The flue draught depends on the suitability of the chimney pot.
It is therefore essential that, if built in a handcrafted way, the exit section is more than twice the internal section of the
flue. As it must always go past the ridge of the roof, the chimney pot must ensure exhaust even in the presence of
wind. (Picture 6).
The chimney pot must meet the following requirements:
•
have an internal section equivalent to that of the chimney.
•
have a useful exit section of double the internal section of the flue.
•
be built so as to prevent rain, snow or any foreign body entering the flue.
•
be easy to inspect, for any maintenance and cleaning operations.
(1) Industrial chimney pot
with
components,
excellent
disposal.
26
2
(for example 20x20cm) for
prefabricated
allowing
flue gas
(1)
(3)
(2) Handcrafted chimney
pot. The correct exit section
must be at least twice the
internal section of the flue,
ideally 2.5 times.
ITALY Termo DSA
(2)
(4)
Max.
A+1/2A
(1) AISI 316 stainless steel flue with
double chamber insulated
material resistant at 400° C.
100% efficiency - excellent.
(2) Fireproof flue with double insulated
chamber and external
lightweight concrete.
100% efficiency - excellent.
(3) Traditional clay flue with square
section and air spaces.
80% efficiency - excellent.
(4) Avoid flues with
rectangular section whose ratio is
different from the design.
Efficiency 40% - mediocre.
(3) Chimney pot for
steel flue with internal
flue gas deflector cone.
7095802 Rev.01 – EN
A+1/2A
A
with
covering in
an internal
Picture 5
Picture 6