28
Example:
An i28C with a
concentric ue gas system
ø60/100mm has according
to the table a maximum ue
straight length of 15m In the
system that is going to be put
in there are 2 x 45° bends, so
the maximum ue gas length
is 15 – ( 2 x -1.3 ) = 12.4m.
L
The total length of the run of the ue is determined by the ue diameter, including for the connection pipe,
elbows ttings and terminal covers etc..
An incorrect dimensioned ue system can lead to disorders. Look at table 9.8.2.a for the choice of the boiler
and the corresponding maximum equivalent ue length.
Explanation table 9.8.2.a:
Concentric ue 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. See example.
Flue dimensions
Rear Flue B (mm)
Min Max
Telescopic ue (FA100105) 280 430
Side Flue B + C (mm)
Min Max
Telescopic ue (FA100105) 285 435
Type i24C i24C iC Economiser 27 Plus i36C i40C iC Economiser 35 Plus iC Economiser 39 Plus
Maximum equivalent length (L) m 15 9 8
45° bend resistance length m -1.3 -1.3 -1.3
87° bend resistance length m -1.9 -1.9 -1.9
Type i24C i28C iC Economiser 27 Plus i36C i40C iC Economiser 35 Plus iC Economiser 39 Plus
Maximum equivalent length (L) m 50 45 40
45° bend resistance length m -1.9 -1.9 -1.9
87° bend resistance length m -3.0 -3.0 -3.0
Tabel 9.8.2.a