8.0 Flue Options
21
8.1
Horizontal Flue Systems
Concentric
The maximum equivalent lengths are 4m
(horizontal) or
(vertical). Their lengths exclude the standard elbow and
flue/terminal assembly (horizontal) and terminal assembly
(vertical).
Any additional “in line” bends in the flue system must be
taken into consideration. Their equivalent lengths are:
Concentric Pipes:
45° bend
0.5 m
93° bend
1.0 m
NOTE:
Flue length is measured from point X to Y as
shown.
IMPORTANT:
All flue systems must be securely
supported at least once every metre. Suitable pipe
supports are available as accessories.
X
Y
X
Y
Plume Displacement 70/110 dia Kit
1M Extensions, 45° & 93° bends
are also available - see Section 9.0
NOTE:
Horizontal flue pipes should always be installed with a 1.5° fall from the
terminal to allow condensate to run back to the boiler.
Y
X
This bend is equivalent to
0.5 metre
Total equivalent length (up to 4m) =
A+B+2x45°Bends
B
A
This bend is equivalent to
0.5 metre
Horizontal
Flue System Examples
FLUES IN VOIDS
Consideration must be given to flue systems in voids
and the provision of adequate access for subsequent
periodic visual inspection.