Ferroli F24
15
Fig. 17
Notes on concentric horizontal installation
To locate the centre of the hole for passing the
pipes through the wall, refer to fig. 13b. Bear in
mind that the two concentric pipes must slope
downwards away from the boiler at a rate of
about 3 mm/m to avoid rainwater entering the
boiler. The concentric pipes making up the air
- flue gas duct must be sealed with the gasket
where they join the boiler (fig. 17). Outside, the
pipes should protrude from the wall between 10
and 60 mm (fig. 17).
3.03.3 Maximum concentric fl ue length
First table below shows the maximum flue lengths available for boilers with concentric systems.
For correct calculation remember to include the reduction for bends on second table. Please refer to
3.02 for use of restrictor.
Maximum flue lenght permissible
100 mm concentric
125 mm concentric
Vertical
Horizontal*
Vertical
Horizontal*
Ferroli F24
m
4
m
3
m
5
m
5
Reduction for bend
100 mm concentric bend 90
°
1 m
100 mm concentric bend 45
°
0,5 m
125 mm concentric bend 90
°
0,5 m
125 mm concentric bend 45
°
0,25 m
*For horizontal Flueing the reduction for appliance bend or turret are already included.
max. 3 m
concentric
100/60
max. 4 m
concentric
100/60
Fig. 18a
Fig. 18b
Between
10-60 mm
