Installing The Flue; Concentric Ducts; Separate Ducts - Baxi Duo-Tec Compact Instruction Manual For Users And Fitters

10. INSTALLING THE FLUE

The boiler is easy and flexible to install thanks to the extensive range of available
accessories, as described below. The boiler has been designed for connection to a
vertical or horizontal coaxial flue-air duct. The boiler can also be used with separate
ducts using the accessory splitting kit.
WARNINGS
C13, C33 The terminals for separate flues must be fitted inside a 50 cm square. Detailed
instructions are provided with the individual accessories.
C53 Do not fit the flue and air duct terminals on opposite walls of the building.
C63 The pressure drop of the ducts must not exceed 100 Pa. The ducts must be certified
for this specific use and for a temperature in excess of 100°C. The flue terminal must be
certified to EN 1856-1.
C43, C83 The flue terminal or flue duct must be suitable for the purpose.
For optimal installation, the accessories supplied by the manufacturer should
be used.
To optimise operating safety, make sure the flue ducts are firmly fixed to the wall with suitable brackets. The brackets must be
positioned over the joints at a distance of approximately 1 metre from one another.
SOME OUTLET DUCT INSTALLATION EXAMPLES AND THEIR RELATIVE MAXIMUM LENGTHS ARE SHOWN IN ANNEX
"SECTION" D AT THE END OF THIS MANUAL.

10.1 CONCENTRIC DUCTS

This type of duct is used to discharge exhaust fumes and draw
combustion air both outside the building and if a LAS flue is fitted.
The 90° coaxial bend allows the boiler to be connected to a flue-
air duct in any direction as it can be rotated by 360° It can also
be used as a supplementary curve combined with a coaxial duct
or a 45° curve.
If fumes are discharged outside the building, the flue-air duct
must protrude at least 18 mm from the wall to allow an aluminium
weathering surround to be fitted and sealed to avoid water
infiltrations.
• A 90° bend reduces the total duct length by 1 metre.
• A 45° bend reduces the total duct length by 0.5 metres.
• The first 90° bend is not included when calculating the maximum available length.
Secure the intake pipes with two galvanised screws with a diameter of 4.2 mm and a maximum length of 19 mm.
Before securing the screws, make sure that at least 45 mm of the pipe is inserted into the gasket (see the figures in annex
"SECTION" D at the end of this manual).
Make sure there is a minimum downward slope of 5 cm per metre of duct towards the boiler.

10.2 SEPARATE DUCTS

For special installations of the fumes inlet/outlet ducts, the
single splitting kit (C), supplied as an accessory, can be used.
This accessory, in fact, can be used to move the inlet and outlet
in any direction. This type of installation makes it possible to
discharge exhaust fumes both outside the building and into
single flue ducts. Comburent air can be drawn in at a different
location from that of the flue terminal. The splitting kit is fixed
to the boiler turret (100/60 mm) and allows the comburent air
and outlet fumes to enter/leave the two separate ducts (80
mm). For further information, read the assembly instructions
supplied with the accessory.
The 90° bend is used to connect the boiler to the inlet and
outlet ducts, adapting them to various requirements. It can
also be used as a supplementary curve combined with a duct
or a 45° bend.
• A 90° bend reduces the total duct length by 0.5 metres.
• A 45° bend reduces the total duct length by 0.25 metres.
• The first 90° bend is not included when calculating the maximum available length.
9 7710400 (01-06/18)