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8.4. Chimney system (Smoke duct, chimney flue and chimney pot)
This chapter is written in accordance with European Standards EN 13384, EN 1443, EN 1856, EN 1457.
The installer must take these Standards and any other local regulations into account.
This manual is in no way to be considered as a replacement for current regulations.
The product must be connected to a suitable smoke exhaust system that guarantees the safe and complete
evacuation of the smoke produced by combustion.
Before positioning the product, the installer must make sure that the chimney flue is suitable.
8.5. Smoke duct, chimney flue
The smoke duct (duct connecting the fire box smoke outlet to the chimney flue inlet) and the chimney flue must,
among other regulatory requirements, in general:
Receive the smoke coming from only one product (it cannot receive the smoke coming from several products);
in some countries there are specific regulations: it is the responsibility of the installer to assess compliance with
local regulations.
Have a predominantly vertical development.
Not have any counter-sloping sections.
Have a preferably circular inner cross-section and in any case with a ratio between sides of less than 1.5.
End on the roof with a suitable chimney pot: it is forbidden to discharge directly from the wall or towards enclosed
spaces, even if outdoors.
Be made of materials with fire reaction class A1 pursuant to UNI EN 13501 or similar national Standard.
Be suitably certified, with an appropriate chimney plate if metal.
Maintain the initial section or vary it only immediately above the product outlet and not along the chimney flue
8.6. Smoke duct
If in metal, it must be provided with CE marking (EN 1856-2) or similar national legislation;
It cannot be made of flexible metal material
To control the flow, a damper is recommended in the event of a draught greater than 25 Pa
8.7. The chimney flue
In addition to the general requirements applicable to the smoke duct and to the chimney flue, the chimney flue:
Must only be used to discharge smoke.
Must be correctly sized to meet smoke evacuation requirements (EN 13384-1 non-exhaustive example)
Is preferably insulated, made of steel and with a circular inner cross-section. If rectangular, the edges must
normally have a radius of not less than 20 mm and a ratio between internal dimensions <1.5.
Normally have a minimum height of 1.5 metres.
Maintain a constant cross-section.
Be waterproof and thermally insulated to ensure draught.
Preferably have a collection chamber for unburnt material and any condensation.
If pre-existing, it must be cleaned, to avoid fire hazards.
As a general guideline, it is advisable to duct the chimney flue if its diameter is greater than 150 mm, the
assessment of which is the responsibility of the technician in charge of sizing the system.
8.8. Ducted system
In addition to the general requirements applicable to the smoke duct and to the chimney flue, the ducted system:
Must operate under negative pressure.
Must be inspectable.
Must comply with local regulations.
