Glow-worm Ultrapower sxi Series Installation And Servicing page 35

10 Twin Flue - Length, Preparation and Installation
10.12 Twin flue
The twin flue system is available as an option when the top
outlet horizontal concentric rear or vertical flue system is not
appropriate, see diagram 10.25.
The system is made up of accessories. The accessories
include terminal assembly, bends 45º and 90º, flue
extensions, fixing bracket and appropriate weather collar, see
diagram 10.26.
The system can provide an independent horizontal air inlet
and flue outlet, horizontal air inlet and vertical flue outlet or
vertical air inlet and flue outlet via a concentric terminal.
NOTE: The air and flue outlets do not have to be equal
lengths. 2x45° bends can replace 1x90° bend if necessary.
The maximum permitted combined straight pipe length is
40 metres plus terminal assemblies, for each 90° or 45° x
2 bends fitted, the maximum length must be reduced by 1
metre.
NOTE: When using 90° bends any horizontal run should be
inclined by a minimum of 44mm/metre (2.5°) towards the
boiler to facilitate condense removal.
Alternatively use 45° bends to avoid horizontal runs in the flue
pipe.
Terminal Position
The clearances for a flue outlet are given in the "Flue Location
and Ventilation" section.
In addition the horizontal air inlet must not be closer than 300
mm from a flue outlet on the same wall or 1200mm from an
opposing flue outlet.
Diagram 10.26
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