Cast iron fireplaces
Instructions for installation, use and maintenance – EN – Rev.07
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c) Each pipe must not exceed 2m of length for natural ventilation and 4m for forced ventilation; it must be
insulated with insulating materials to avoid noise and dispersion of heat
.
d) The openings must be positioned at a height not lower than 2 m from the floor to avoid that hot air at
output meets people.
e)
The canalization pipes must all have an equal length in order to avoid different quantities of air
distributed from each outlet
.
(see Figure 12 -Figure 13)
7. CONNECTION TO THE FLUE / AIR FOR COMBUSTION (external air intake)
The connection to the stack must be performed with stiff pipes in aluminized steel with a minimum
thickness of 2 mm or in 316 stainless steel with a minimum thickness of 1 mm.
It is forbidden to use metallic pipes or pipes in asbestos cement since they jeopardize the safety of
the fitting itself, considering that they are subject to tears or breaks resulting in leaks of smoke.
The exhaust pipe must be air-tight fastened to the stack and can have a maximum inclination of 45°; th is to
avoid excessive deposits of condensate produced in the initial start-up phases and/or the excessive
gripping of soot and moreover it avoids the slowing down of the smokes at output.
The failed tightness of the connection can cause the malfunction of the device.
The internal diameter of the connection pipe must be equal to the external diameter of the smokes stub
pipe of the device. This is assured by the pipes complying with DIN 1298.
The depression in the stack should be - 14 Pa (=1.4 mm of column of water).
The measurement has always to be carried out with hot device (rated thermal performance).
When the depression exceeds 17 Pa (1.7 mm of column of water), it is necessary to reduce the same by
installing an additional draught regulator (butterfly valve).
IMPORTANT
:
When using metallic pipes, they must be insulated with proper materials (coatings in insulating
fibers resistant up to 600°C) in order to avoid det erioration of walls or of the counter-hood.
It is necessary to ventilate continuously the space included between the upper part, the sides of the device
and the deflector of the fire-proofing material of the hood.
For this reason, it is necessary to foresee an intake of air from the bottom (intake of fresh air) and a high
output (output of hot air).
The spaces foreseen for the circulation of air indicated in Figure 14 - Figure 15 represent the minimum
requirements:
Figure 12
Figure 13
