11.8 Air and Flue Duct Preparation
The method of installation of the flue system may be varied to
suit the actual site conditions. The instructions for connecting
and fixing the ducts must, however, be strictly followed.
Remove all packing material from the flue components.
Fit the flue restrictor ring by unscrewing the flue spigot from the
boiler. Refer to Fig. 22.
The standard telescopic flue assembly is suitable (without
cutting) for flues from 425mm up to 725mm measured from the
centre-line of the boiler flue outlet to the outer face of the wall.
Refer to Fig.23.
The minimum length of the standard flue, after cutting is 275mm.
If L is greater than 725mm then extension duct kit/s will be required
- each kit extends the flue by 750mm up to a maximum of 4000
mm for natural gas boilers and 2500mm for LPG. See table below.
EXTENSION
MAXIMUM FLUE LENGTH mm
1
1475
2
2225
3
2975
4
3725
5
4000
11.9 Measure and Cut the Ducts.
General
: Cut the ducts as necessary, ensuring that the cuts are
square and free from burrs. Always check the dimensions before
cutting.
Measure the distance L. Refer to Fig. 23, 24, 25 and 26.
The standard flue can be telescopically adjusted to any length
between 425mm and 725mm measured from the centre of the
turret without the need to cut the ducts.
Fix the flue assembly together using the self-tapping screws
provided. Refer to Fig. 23.
It will only be necessary to cut the standard assembly if L is less
than 425mm. Cut the flue turret assembly and the terminal
assembly by the same amount eg. if L=350 – remove 75mm
(425-350) from each assembly.
14
Fig. 22. Flue spigot and restrictor
1
2
3
4
Fig. 21. Inner case and facia fixing
Fig.23. Standard flue assembly
L
Fixing screw
Flue
turret
assembly
Appliance casing
Telescopic adjustment
Terminal
assembly
3
1. Inner casing cover
2. Cabinet fixing screws (4)
3. Inner casing cover fixing screws (2)
4. Inner casing cover fixing screws (2)
5. Facia control panel
6. Controls connector cover
7. Controls connector cover fixing screws (2)
8. Programmer (optional)
9. Facia control panel fixing screw
10. Top support lug (2)
11. Bottom support lug (2)
1
4
5
7
2
6
7
10
9
8
2
11
RESTRICTOR RINGS
Flue length
24Si II
28Si II
Horizontal up to 725mm
76mm
78mm
Horizontal above 725mm
None
None
LPG Horizontal up to 725mm
76mm
77mm
Vertical terminal length only 1200mm 78mm 82mm
Vertical flue greater than 1200mm None None
1. Flue spigot fixing screws
2. Flue spigot
3. Restrictor ring
4. Flue spigot fixing holes