Glow-worm ULTRACON 18SXI Installation And Servicing Manual page 23

10 Standard Flue - Length, Preparation and Installation
10.6 Flue Length
The maximum permissable horizontal flue length is 10 metres
plus the flue terminal assembly, this can be achieved by use
of the accessories, see diagram 10.12.
However should additional 90 o or 2 x 45 o elbows be used
then the length MUST be reduced by 1metre.
The diagram 10.10 shows the length achievable by using the
kit A2043400.
Standard Horizontal Flue
75 min. to 554 max.
WALL THICKNESS
87min
OUTSIDE
WALL FACE
NOTE. If necessary, it is permitted to increase
this dimension to 600mm max.
NOTE. If necessary, it is permitted to
increase this dimension to 600mm max.
87min
Max flue length 730mm
5mm
min.
clearance
A
OUTSIDE INTERNAL
WALL FACE SURFACE
Max. distance from outside
wall face to min clearance.
LH - 486mm
RH - 514mm
112
176
BOILER
MOUNTING WALL
239 211
C
L
FLUE
A
Min. distance from outside
wall face to min clearance.
LH/RH - 75mm
Diagram 10.10
When extension pipes are used the flue system must be
designed to have a continuous fall to the boiler of at least
2.5 o 44mm/metre to allow condensate to run back into the
boiler and out via the condensate drain.
The flue can be installed from inside the building, when
access to the outside wall face is not practicable.
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