33
ENGLISH
INSTALLER
b
Maximum straight length is the maximum length of
the flue without bends, terminals or joints.
b
All lengths are referred to atmospheric pressure at
sea level.
SEALED INSTALLATION (TYPE C)
Coaxial flues (Ø 60/100)
Coaxial flues can be oriented in whatever direction is
most convenient for the room, provided the maximum
lengths specified alongside are respected.
b
Ensure that the flue gas vent pipe has a 1% slope
towards the boiler.
b
Use of flue pipes longer than the maximum spec-
ified alongside leads to a loss of heat output from
the boiler (see table alongside).
b
The boiler automatically adapts its ventilation sys-
tem to suit the type of installation and the length of
the flue. Never obstruct or partly choke the combu-
rent air intake pipe.
b
Use only flues specifically designed for use with
condensing boilers. Follow the instructions pro-
vided in the flue pipe kit to install the flues.
20
40 6080
100
4
3 2 1
0
0
120
°C
0
120
20
100
40
80
60
20
40 6080
100
4
3 2 1
0
0
120
°C
0
120
20
100
40
80
60
20
40 6080
100
4
3 2 1
0
0
120
°C
0
120
20
100
40
80
60
20
40 6080
100
4
3 2 1
0
0
120
°C
0
120
20
100
40
80
60
20
40 6080
100
4
3 2 1
0
0
120
°C
0
120
20
100
40
80
60
20
40 6080
100
4
3 2 1
0
0
120
°C
0
120
20
100
40
80
60
20
40 6080
100
4
3 2 1
0
0
120
°C
0
120
20
100
40
80
60
20
40 6080
100
4
3 2 1
0
0
120
°C
0
120
20
100
40
80
60
20
40 6080
100
4
3 2 1
0
0
120
°C
0
120
20
100
40
80
60
20
40 6080
100
4
3 2 1
0
0
120
°C
0
120
20
100
40
80
60
20
40 6080
100
4
3 2 1
0
0
120
°C
0
120
20
100
40
80
60
C13
C13
C13
C23
C53
B23P
B53P
C83
C63
C33
C43
B23P
Upstream fan. Comburent air intake
directly from the room where the
boiler is installed. Flue gas vent via
horizontal or vertical flues designed
to operate at positive pressure, with
air ventilation to room.
B53P
Upstream fan. Comburent air intake
directly from the room where the
boiler is installed. Flue gas vent via horizontal
or vertical flues designed to operate at positive
pressure, with air ventilation to room.
C13
Concentric wall vent. Twin flue pipes can also be
used, but the wall through-pipes must be concen-
tric or located close enough to be subjected to
similar wind conditions.
C23
Concentric vent to shared flue (air intake and flue
gas vent via same concentric pipe).
C33
Concentric roof vent. Outlets as for C13.
C43
Vent and air intake via shared twin pipes, subject-
ed to similar wind conditions.
C53
Separate wall or roof vent and air intake, in areas
of different pressure but never on opposite walls.
C63
Upstream fan. Comburent air intake and flue gas
vent without flue terminals.
C83
Upstream fan. Comburent air intake through wall
and flue gas vent to roof.
b
In Italy, refer to Normative vigenti
Horizontal
Maximum straight length of
coaxial flue Ø 60/100
(m)
Pressure drop
(m)
45° bend 90° bend
7,80
0,5
0,85
Vertical
Maximum straight length of
coaxial flue Ø 60/100
(m)
Pressure drop
(m)
45° bend 90° bend
7,80
0,5
0,85
