Installation & Servicing instructions ATAG iS-Range
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Example:
An iS24 with a
concentric flue gas system
ø60/100mm has according
to the table a maximum flue
straight length of 13m In the
system that is going to be put
in there are 2 x 45° bends, so
the maximum flue gas length
is 13 – ( 2 x -1.0 ) = 11 m.
ø60/100mm
L
in m
iS 12
Maximum straight length 60/100
13
iS 15
87° bend resistance length
1.6
iS 18
45° bend resistance length
1.0
iS 24
iS 32
Maximum straight length 60/100
6
iS 40
87° bend resistance length
1.6
45° bend resistance length
1.0
Concentric flue system ø60/100mm
Dimensions flue gas system and air supply system
Table 9.8.2.a
L
9.8.2 Dimensioning of the flue gas and air intake duct
The total length of the run of the flue is determined by the flue diameter, including for the connection pipe,
elbows fittings and terminal covers etc..
An incorrect dimensioned flue system can lead to disorders. Look at table 9.8.2.a for the choice of the boiler
and the corresponding maximum flue lenght.
Explanation table 9.8.2.a:
Concentric flue gas system:
maximum noted length L = distance between boiler (from elbow or vertical adapter) and the end of terminal
When using bends the noted value behind every bend should be deducted from the maximum straight
length.
Flue dimensions
Rear Flue
B (mm)
Min
Max
Telescopic flue (FA100100)
280
430
Side Flue
B + C (mm)
Min
Max
Telescopic flue (FA100100)
285
435
Rear Flue
L = wall thickness (B) + 150mm
Side Flue
L = wall thickness (B) + distance between boiler and wall (C) + 150mm
If the length L is more than 580mm rear flue or 585mm side flue, then a
Horizontal flue fixed length 1000mm (60/100mm) with lock function elbow
(FA100250) will need to be used instead, up to 810mm.
L
Figure 9.8.2.a