Maximum Flue Length (L); Additional Flue Parts; Standard 100 Mm Flue Systems - Worcester GB162-50 Installation And Servicing Instructions

Installation
8.3.3

Maximum Flue length (L)

The maximum pipe length (L) of the air supply and flue gas exhaust pipes
for the condensing gas system boilers is determined by the total
pressure loss of all components in the flue system.
Maximum length of horizontal or vertical extensions for 100/150 flue
system ( fig. 30 and fig. 31). For flue length see table 6.
L
Fig. 30 Vertical flue length
B
A
Fig. 31 Horizontal flue length
[A] Distance from centre of flue to inside rear wall
[B] Distance from centre wall bracket to centre of flue elbow
[L] Distance from centre of flue to outside wall
Take the flue pipe clearances into account when planning the layout of
the place of installation ( subsection 8.3.1: "Siting the flue terminal"
on page 20).
Maximum wall thickness without extensions is 415 mm. Maintain a
minimum side clearance of 8 mm ( fig. 28).
22
6 720 648 726-030.1TD
L
6 720 648 726-031.1TD
8.3.4

Additional flue parts

The additional flue parts listed can be ordered from your supplier.
Flue size 100/150 and 80/125
GB162 Maximum flue length [m]
concentric flue system
100/150
50 20
65 20
80 18
100 18
Table 6 Max. flue lengths, incl. wall/roofterminal in meters
GB162 Reduced flue length [m]
concentric flue system
100/150
bend extension
45° 90° 0.5m
50 1.2 2.1 0.5
65 1.2 2.1 0.5
80 1.2 2.1 0.5
100 1.2 2.1 0.5
Table 7 Reduced flue lengths in meters
1) For every bend or extension the max. flue length (L) has to be reduced.
The total reduction length must never exceed the
maximum flue length.
Weathering slates for 100/150 and 80/125
Flat roof, pitched roof.
8.3.5

Standard 100 mm flue systems

The standard concentric flue system provides for a max. horizontal
straight length ( table 6, subsection 8.3.4). Full instructions for
fitting this flue are in subsection 8.3.6: "Installation of the horizontal
flue" on page 23.
Important: Any horizontal flue system fitted to a
condensing boiler must be inclined towards the
appliance at an angle of 52 mm per metre length to
prevent condensate dripping from the flue terminal.
This means that the clearance above the appliance must
be increased to match the duct length. See fig. 6 on
page 12.
80/125
7,7
7.7
–
–
1)
concentric flue system
80/125
bend extension
1m 45° 90° 0.5m 1m
1.0 0.9 1.9 0.5 1.0
1.0 0.9 1.9 0.5 1.0
1.0 0.9 1.9 0.5 1.0
1.0 0.9 1.9 0.5 1.0
6720813171 (2015/04)