7
3.12 Flue gas discharge and air suction
Observe local legislation regarding flue gas discharge.
The discharge of flue gas is guaranteed by the centrifugal fan fitted in the
boiler.
The boiler is supplied without the flue gas outlet/air suction kit, since it is
possible to use the accessories for appliance with a forced draught sealed
chamber that better adapts to the installation characteristics.
For flue gas discharge and the restoration of boiler combustion air, it is
essential to use only our original, specific pipes for condensation boilers,
and to ensure that the connection is made correctly (as indicated in the
instructions supplied with the flue gas accessories).
The boiler is a C-type applian ce (with airtight chamber), and must therefore
have a safe connection to the flue gas discharge pipe and to the combustion
air suction pipe; these both carry their contents outside, and are essential
for the operation of the appliance.
Both concentric and twin terminals are available.
The boiler is designed to take in and dispose of flue gas condensate
and/or meteoric water condensate deriving from the flue gas
discharge system. It does this via its own drain-tap, if an external
drain-tap is not fitted during the design or installation phase.
WARNING: if a condensate relaunch pump is installed, check the
technical data (provided by the manufacturer) regarding output, to
ensure it operates correctly.
“FORCED OPEN” INSTALLATION (TYPE B23P-B53P) - fig. 25
Flue gas discharge pipe ø 80mm
To arrange this configuration, you must use the specific connection point
supplied as an accessory.
For installation, follow the instructions supplied with the kit.
In this case, the combustion air is picked up from the boiler installation
room (which must be a suitable technical room with proper ventilation).
The non insulated flue gas outlet pipes are potential sources of danger.
Arrange the flue gas discharge pipe so it slopes by 1% towards the
boiler.
m
aximum length of the flue gas discharge
pipe ø 80mm
pressure drop
45° curve 90° curve
30 m
1 m
1,5 m
“Straight length” means without bends, drainage terminals or joints.
Concentric pipes (ø 80-125mm) - fig. 27
To connect the concentric pipes, use the specific adaptor supplied as an
accessory.
The concentric pipes can face in the direction most suitable for installation
requirements, but special attention should be paid to the external temperature
and the length of the pipe.
Arrange the flue gas discharge pipe so it slopes by 1% towards the boiler.
Non-insulated outlet pipes are potential sources of danger.
The boiler automatically adapts the purging to the type of installation
and the length of the pipe.
Do not obstruct or choke the combustion air suction pipe in any way.
For installation, follow the instructions supplied with the kit.
“AIRTIGHT” INSTALLATION (TYPE C)
The boiler must be connected to concentric or twin flue gas discharge pipes
and air suction pipes, both leading outdoors. The boiler must not be operated
without them.
Concentric pipes (ø 60-100mm) - fig. 26
To connect the concentric pipes, use the specific adaptor supplied as an
accessory.
The concentric pipes can face in the direction most suitable for installation
requirements, but special attention should be paid to the external temperature
and the length of the pipe.
s
traight length of concen-
tric pipe ø 60-100mm
Horizontal
Vertical
pressure drop
45° curve 90° curve
1,85 m
2,85 m
1,3 m
1,6 m
Flow rate (l/h)
Residual head (m.C.A.)
0,00
0,50
1,00
1,50
2,00
2,50
3,00
3,50
4,00
4,50
5,00
5,50
6,00
6,50
7,00
0
100
200
300
400
500
600
700
800
900
1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000
Pr
ev
al
en
za
re
sidu
a
(m
C.
A.
)
Portata (l/h)
Arrange the flue gas discharge pipe so it slopes by 1% towards the
boiler.
Non-insulated outlet pipes are potential sources of danger.
The boiler automatically adapts the purging to the type of installation
and the length of the pipe.
Do not obstruct or choke the combustion air suction pipe in any way.
For installation, follow the instructions supplied with the kit.
s
traight length of concentric pipe ø 80-125mm
pressure drop
45° curve 90° curve
4,85 m
1 m
1,5 m
Twin pipes (ø 80mm) - fig. 28-29
The twin pipes can face in the direction most suitable for installation re-
quirements.
For installation, follow the instructions supplied with the specific accessory
kit for condensation boilers.
Arrange the flue gas discharge pipe so it slopes by 1% towards the
boiler.
The boiler automatically adapts the purging to the type of installation
and the length of the pipes. Do not obstruct or choke the pipes in any
way.
The use of longer pipes reduces the boiler output.
m
aximum straight length of twin pipes ø
80mm
pressure drop
45° curve 90° curve
20 + 20 m
1 m
1,5 m
“Straight length” means without bends, drainage terminals or joints.
