14
14
2.2 Flue
The flue is an all-important element for fireplace’s proper
functioning and must comply with the standards:
EN1856-1 -Fireplaces: requirements for metal fireplaces-
Part 1:Products for fireplace systems.
EN1856-2 -Fireplaces: requirements for metal fireplaces-
Part 2: Internal ducts and metal exhaust pipes
EN10683 -Installation requirements
The cross section of the flue must be that indicated in the
fireplace technical characteristics. Each stove must have its
own flue, which must not be shared by any other emissions
(fireplaces, boilers, stoves, etc.)
The dimensions of the flue depend on its height, to be measured
from the fireplace to the bottom of the chimney cap.
To ensure adequate draught, the fume outlet area of the cap
must be double the cross section area of the flue. The pipe
used to exhaust the fumes generated by the natural-draught
fireplace must:
- be fumetight, impermeable and adequately insulated
according the conditions of use (see UNI 9615).
- be made from materials able to withstand the normal
mechanical stresses, heat, and be resistant to the action of
fumes and possible condensate.
- be mainly vertical, with deviations from the axis not exceeding
45°.
- be installed at a suitable distance from combustible or
flammable materials, by an air gap or suitable insulation
- preferably have a round internal section: square or rectangular
sections must have rounded corners with radius of at least 20
mm.
- have a uniform, free and independent internal section.
- have the rectangular sections with a max. ratio between the
sides of 1.5:1.
An antiwind-type cap is advisable. If the flue is installed
externally, it must be insulated to prevent the cooling of fumes
and the formation of condensate. The same applies to the
section from the roof to the chimney cap.
For the connection between the fireplace and flue, or in the
presence of branches or bends, or for easier, quick and safe
installation, it is advisable to use double-wall stainless steel
pipes without insulation inside hoods. Non-combustible materials
resistant to the fumes and their possible condensate must be
used for installing the fume ducts.
The use of asbestos cement pipes to connect appliances to the
flue is prohibited.
The fume ducts must not cross rooms in which the installation
of combustion appliances is prohibited. The fume ducts must
be installed in such a way as to ensure fume tightness when
the fireplace is in negative pressure operating conditions and
to avoid the formation of condensate and its conveyance to
the unit.
Horizontal sections should be avoided as much as possible.
For exhaust pipes which must reach ceiling or wall outlets
that are not coaxial with respect to the fireplace fume outlet,
changes of direction must be made using open elbows not
exceeding 45° (see
F
ig
. 1
).
Do not use elements sloping in the other direction. The flue must
be designed allow removal of soot and brush cleaning. The
exhaust pipe must have a uniform cross section. Any changes
in section are only permitted at the generator outlet; reduction
adapters must not be used at the connection with the flue.
Do not route other air supply and system pipes inside the
exhaust pipes even if the latter are oversized.
Do not support the weight of the flue on the stove/fireplace
connection. Use special brackets or separate supports.
Other stoves, fireplaces, boilers or air extractors must not
be installed in the same room (excluded of the type “C”
according to UNI 10683).
Minimum height of exhaust pipe: 3 metres.
F
ig
. 1
Summary of Contents for UNIVERSAL JOLLY Maxi
Page 23: ...21 NOTES ...
