44
• Assemble the flue such that there
is a gap of about 10 mm between
each air duct, which will ensure
the correct flue duct penetration
into the flue sockets of 30 mm. All
flue sockets should point towards
the flue terminal.
• Measure the air duct (from the
end with the 3 fixing holes) and
mark the air duct to this length.
• Take the extension(s) to be
shortened and remove the
3 screws. Separate the ducts.
Note: For assembly reasons do not
shorten any air duct to a length of
less than 100 mm. If necessary
shorten two adjacent extensions to
achieve the overall required length.
• Cut the air duct square.
• Refit the flue duct into the air duct
and secure using the 3 screws.
• Cut the flue duct as detailed in
figure 5.5.
• When cutting the air and flue
ducts it is important to remove any
burrs with a file, this ensures easy
fitting of the ducts and prevents
any rough edges from damaging
the flue seals.
• Care should be taken not to
scratch the white surface of the air
duct.
• If the installation requires the use
of air/flue duct extensions,
additional bends or elbows refer
to the sections on pages 45 - 47.
• Install the flue extensions by
working from the installed air/flue
and terminal accessory back
towards the boiler.
• The joints between the flue duct
sections are made by pushing the
flue duct spigot into the socket of
the flue duct extension by 30 mm.
This is achieved when the gap
between the air duct sections is
10 mm.
• All sockets should point towards
the flue terminal.
• The joints between the air duct
sections should be clamped using
the air duct clamps.
• Ensure that the air duct clamps
are positioned centrally.
INSTALLATION OF THE VERTICAL ROOF DUCT
10 mm
Length of air duct
10 mm
Fig. 5.4
25 mm
Mark flue duct here
15 mm
Fig. 5.5
