Do not connect the external air vent to the stove through piping. If there are other heating or suction appliances in the room, air vents must
guarantee an air volume required for the proper operation of all devices.
Only sealed equipment (e.g. C type gas equipment, according to the UNI 7129 Standard) or equipment that does not cause lower pressure
compared with the external environment can pre-exist or be installed in the place where the stove must be installed.
Extractor fan can cause functioning problems to the stove when they are installed in the same room or space where the appliance is found.
Flue and connection to the same flue - Chimney
The flue is a fundamental component for correct functioning of the stove. The minimum section of the flue must be that indicated in the stove technical
features (80 mm). Each stove must be equipped with its own flue, without other intakes (boilers, chimneys, stoves etc...). Flue dimensions are closely related
to its height, which must be measured from the stove flue gas outlet to the chimney base. In order to guarantee draught, the chimney flue outlet surface must
be twice as big as the flue section.
The combustion product exhaust pipe, which is generated by the forced draught appliance, must respond to the following requisites:
Combustion products sealed, waterproof and suitably isolated and insulated in the same way as the conditions of use (cf UNI 9615);
Made of suitable materials in order to resist to normal mechanical stress, heat, action of the combustion products and condensation if any;
Upward alignment after the vertical tract throughout the remaining pathway with 5% minimum gradient. The sub-horizontal alignment part must not have
a length greater than ¼ of the effective height of the flue or chimney and it must not however be longer than 2,000 mm;
Preferably circular internal section: squared and rectangular sections must have rounded angles with radius larger than 20 mm;
Constant, free and independent internal section;
Rectangular sections with 1.5 maximum ratio between the sides;
If the flue is installed externally or in a cold room (e.g. stove room) it is absolutely necessary that it is insulated to avoid the flue gas cooling
and condensate forming;
Elements of non-combustible material must be used for the assembly of the flue gas pipes (which go from the appliance to the flue inlet), which are
suitable for resisting combustion products and their condensation;
It is prohibited to use fibre cement pipes to connect the appliances to the flue;
Flue pipes must not pass through places in which the installation of combustion appliances is prohibited;
The assembly of flue pipes must guarantee the sealing against flue gas for the appliance operation conditions when in low pressure;
The assembly of horizontal tracts is forbidden;
It is prohibited to use tilted elements;
The flue gas pipe must allow the recovery of soot or be cleanable and must have a constant section;
It is prohibited to make other air intake channels and pipes for plant engineering transit inside the flue gas pipes, even if over-dimensioned.
The chimney is a device crowning the flue, used to ease dispersion of combustion products.
It must satisfy the following requisites:
Have a useful outlet section that is not less than the double of that of the flue on which it is inserted;
Be conformed in a way to prevent the penetration of rain and snow into the flue;
Be built in a way that, also in the case of winds from every direction and inclination, to ensure combustion exhaust.
The outlet height (where height means that which corresponds to the top of the flue, independently of any chimneys) must be outside of the so-called reflow
area in order to prevent the formation of counter-pressures, which prevent free exhaust of the combustion products in the atmosphere.
It is therefore necessary that the minimum heights, indicated in the following figures, are respected:
Dista nce > 5 m
Technical
volume
Fig. A
Dista nce < 5 m
20
Distanc e> 1,85 m
Distanc e< 1,85 m
6
Reflow zone