9 – SMOKE DISCHARGE TUBE AND VENTILATION OF THE ROOMS
9.1 FOREWORD
Due to the frequent accidents caused by poor functioning of flue outlets installed in private dwellings, we have
prepared the following paragraph to assist the installer in his inspection of the parts concerned with eliminating the
gases produced by combustion.
The flue outlet must comply with UNI 10683 and be built in accordance with the requirements set out in Italian Decree
No. 37 of 22 January 2008, respecting the reference values expressed in the standard; in particular, the flue outlet
must conform to fire prevention standards (it must therefore be capable of withstanding a possible fire action: in such
a situation contact the fire department immediately). This chapter is not intended to replace UNI 7129, UNI 10683
and EN 14785 standards to which it refers. The qualified installer must in any case be fully aware of these standards
and any amending versions. It is important to carefully follow the instructions included in these standards: failure to
observe these instructions could cause serious damage to the product, to the system, to objects and to persons using
the generator.
9.2 ROOM VENTILATION
ATTENTION: The presence of extraction fans or similar appliances, if operating in the same room or space in which
the product is installed, could cause problems for the correct operation of the product.
ATTENTION: do not obstruct the vents or the air inlets on the appliance.
The room where the appliance is installed must have a good air flow to guarantee air for the appliance for the combustion process
and for ventilation of the room. The natural air flow must take place directly through permanent openings on the outer walls or
through single or multiple ventilation ducting.
The ventilating air must come from outside and if possible, away from sources of pollution. The openings in the walls must comply
with the following conditions:
• have an unobstructed section of at least 6cm² for each Kw of installed thermal power, with a minimum limit of 100cm²;
• be made in such a way that the vent openings, both on the inside and outside of the wall, cannot be obstructed;
• be protected with grills or similar systems that do not reduce the opening section indicated above;
• be situated at a height near floor level and they must not obstruct the correct operation of the combustion product discharge
devices; if this position is not possible the section of the ventilation openings must be enlarged by at least 50%.
9.2.2 VENTILATION OF THE ADJACENT ROOMS
The air flow can also be obtained from an adjacent room as long as:
• the adjoining room is equipped with direct ventilation in compliance with the paragraphs described above;
• only appliances connected to the exhaust pipe are installed in the room that is ventilated;
• the adjoining room is not used as a bedroom or a common area of the building;
• the adjacent room is not a room with a fire hazard, such as storage sheds, garages, combustible material store rooms, etc...;
• the adjoining room does not become a vacuum compared to the room to be ventilated due to a reverse draught effect (the reverse
draught can be caused by the presence in the room of either another heating appliance running on any type of fuel, a fireplace, or
any suction device, which have not been provided with an air intake)
• the air flow from the adjoining room to the room to be ventilated is unobstructed through the permanent apertures having an
overall net section of no less than that indicated above. These apertures can be obtained by enlarging the space between the door
and the floor.
9.3 SMOKE OUTLET
The smoke channel, the exhaust pipe, chimney and flue outlet (defined as the system for the evacuation of combustion
products), are parts of the heating system and they must comply with the legislative requirements of the Ministerial
Decree DM 37/08 (ex Italian Law 46/90) and to the applicable specific installation regulations, according to the type of
fuel. Fireplaces, stoves and barbecues must not be installed in locations where gas appliances type A and type B are
present and operating (for the classification see UNI 10642 and UNI 7129). The connection between the appliance and
the flue outlet must only receive exhaust from one heat generator.
9.3.1 CHIMNEY TYPES
The following types of chimneys, constructed as described, are possible:
• System: Chimney installed using a combination of compatible components (flue liner, insulation, outer casing etc…), constructed
or specified by a single manufacturer and CE certified in accordance with the applicable standard;
• Composite chimney: Chimney installed or constructed on site using a combination of compatible components such as flue liner
(wall directly in contact with the smoke), and possibly also insulation and outer casing (wall) that may be supplied by different
manufacturers or by the same manufacturer.
• Relining: operation involving the installation of a specific pipe in an existing shaft (even if newly constructed) made of non-
combustible materials, free from obstructions and for single use.
