2.3 Air inlet
The boiler must have the combustion air needed to ensure proper operation, through external air inlets, and
specifically:
-a wall air inlet of at least of 100 cm², communicating with the outside and suitably protected externally by a grille,
must be provided near the boiler;
-or by connection directly to the outside with a suitable pipe of inside diameter 50mm and max. length 1.5 m suitably
protected at the end.
-or through the room adjacent to that of installation provided the air is free to flow through permanent openings
communicating with the outside, meeting the requirements described above. The adjacent room must not be subject
to a lower pressure than the outside environment due to the draught effect created by the presence of other possible
units or suction devices. The adjacent room can not be used as a car garage, for storing combustible material or for
activities with fire risk.
The inlet connection or air intake (diam. 50/60 mm round section) is located at the back of the boiler and is suitably
protected by a grille incorporated in rear sheet metal and removable if necessary; it must also ensure a flow of clean
air, free of pollutants, for regular combustion at maximum power.
2.4 Fume exhaust
Fumes can be exhausted through a connection to an approved flue.
-The installer must check the efficiency and state of the flue and its conformity with the local, national
and European regulations.
-Only certified pipes and connections with adequate seals guaranteeing their tightness must be used.
-Make sure there is an inspection device at the bottom of the flue for periodical checking and cleaning,
to be done every year (compulsory).
-Make sure an approved antiwind cap is installed at the top of the flue.
-Flexible metal tubes or fibre cement pipes are prohibited.
-In case of fire, turn the boiler off, promptly call the fire department,and avoid continual attempts to
extinguish it.
2.4.1 Types of installations
Listed below are definitions and requirements for correct installation of an
exhaust flue in accordance with Italian Standard UNI10683:
FLUE : a vertical duct for collecting and expelling, at an appropriate height
from ground, the fumes coming from a single unit and, where permitted,
more than one.
FLUE technical requirements :- it must be fumetight, isolated and
insulated depending on its use;
- it must have a mainly vertical path with axis deviation < 45°;
- it must be placed at a suitable distance from flammable materials by
means of insulation or air gap;
- it must preferably have a continuous, free and independent round internal
section;
- it is advisable for the flue to have an inspectionable chamber for the
collection of solid materials
- and any condensate, placed under the beginning of the fume duct.
FLUE CONNECTION or DUCT: duct or connection element between the unit and flue for evacuation of fumes.
DUCT technical requirements: - it must not cross rooms where the installation of combustion units is not allowed;
- flexible metal tubes or fibre cement pipes are prohibited;
- the use of counter-sloping elements is prohibited;
- horizontal sections must have an upward slope of at least 3%;
- the length of the horizontal section must be minimal and not more than 3 m;
- there must not be more than 3 changes of direction without the T union;
- with change of direction > 90° a max. of 2 bends can be used with length in horizontal projection not exceeding 2 m.
- the fume duct must have a continuous section and allow the recovery of soot.
47
Antiwind grille
Comignolo
antivento
Flue
Canna
fumaria
Min. distance 0.2m
Distanza minima
NATURFIRE 30-35-39 HR
Flue
Raccordo
connection
fumi
Inspectiona
Camera
ble chamber
ispezionabile
Outside air inlet
Presa d'aria
min. 100 cm²
esterna
2
min.100 cm