7
Twin Pipe Flue Systems
HORIZONTAL TERMINAL POSITIONING
Separated flue duct terminal
Separated air duct terminal
Flue and air ducts located together on the same wall
Fig. 10
Fig. 8
Fig. 9
2.
Vertical terminal (see Fig. 3)
i)
Refer to Fig. 3 for positioning of the vertical terminal in the roof.
Note: Under no circumstances must the terminal be shortened in length.
ii)
To enable direct connection of the flue and air ducts to the terminal the duct centres must be 120 mm apart.
iii) At the required position cut a hole and/or remove tiles so that there is at least a 170 mm diameter hole in the roof.
Ensure there is at least a 25 mm gap between the outer duct and any combustible material.
iv) Fit a weathering slate, suitable for a 120 mm outside diameter flue, over the hole in the roof.
v)
Fit the terminal assembly into the weathering slate and place it in position, ensuring the minimum distances given
in Fig. 3 are maintained.
vi) After assembly of the ducts to the terminal, ensure it is not possible to disengage any part of the flue assembly
and ensure the weathering slate is fitted correctly.
3.
Ridge tile kit (see Fig. 4)
As supplied, the ridge tile kit enables the 80 mm flue duct to be connected to a standard ridge terminal. It is only for
connection to the flue products exhaust duct on the boiler.
The air duct should terminate horizontally, preferably on an external wall or via a purpose designed ducting system or
area that will always ensure a permanent and adequate air supply (refer to BS 5440:1).
60
100
60
100
Min. 120
Min. 120
Min. 300
Flue
Air
Air
