Ariston Benchmark System A 24 RFF Installation And Servicing Instructions page 24

12.4 Fitting the twin pipe flue (Ø80/80) (continued)
Fig. 27
In the event that twin flue pipes are used, and the boiler has a side clearance of less than 60mm from the wall, it is necessary
to cut a larger diameter hole for the flue pipe, this should be ø10 cm, this will then allow for easier assembly of the air intake
elbow and the tube outside the wall (see Fig. 28).
Concentric outlet
TABLE
(Type 1, Type 2, Type 3)
A
Concentric outlet
TABLE
B
(Type 2, Type 3)
TABLE
C
For coaxial systems, the maximum development value, mentioned in the table above also takes into account an elbow.
For twin flue systems the maximum development value, mentioned in the table includes the exhaust gas/air intake terminal.
Type 5 outlets should respect the following instructions:
1- Use the same ø 80 mm flue pipes for the gas intakes and exhaust gas ducts.
2- If you need to insert elbows in the gas intake and exhaust gas ducts, you should consider for each one the equivalent length
to be included in the calculation of developed length.
3- The exhaust gas duct should jut above the roof by at least 0.5 m.
4- The intake and exhaust gas ducts in Type 5 must be installed on the same wall, or where the exhaust is vertical and the air
intake horizontal, the terminals must be on the same side of the building.
Twin flue length diagram
(24 and 30 kW)
24
123,5
25
60/100
24 , 30 kW
80/125
24 , 30 kW
(Type 1)
24 , 30 kW
Twin flue outlet
24 , 30 kW
Type 4
80/80
Type 5
80/80
Min length
0.3 m
Min length
0.3 m
0.3 m
Min length
10 m
(35m air / 35m exhaust)
10 m
(35m air / 35m exhaust)
Minima HE 24, 30 & 35 FF
70
60
50
40
30
Working area
20
10
0
0 10 20
Air inlet length in meter
60 mm
Max. length
equivalency for
45
10m
elbow
90
elbow
Max. length
45
30 m
elbow
90
35 m
elbow
Max. length
70 m 45
elbow
70 m 90
elbow
30 40 50
Fig. 28
Length
o
0.5 m
o
1 m
o
0.5 m
o
1 m
o
1.4 m
o
2.2 m
140
120
100
80
60
40
20
0
60