Installation
35
MAXXfl o EVO
4.8 MAXIMUM FLUE LENGTHS
Permitted Flue Equivalent Length (FEL) for type B
23
fl ue
=
40 metres
Permitted Flue Equivalent Length (FEL) for type C
13
, C
33
fl ue
=
18 metres
Permitted Flue Equivalent Length (FEL) for type C
53
fl ue
=
36 metres
The fl ue duct can discharge either vertically or horizontally by selection of the correct fl ue terminal. The fl ue
system can be fi tted with 90
O
and 45
O
bends, as well as extensions.
Each fl ue accessory such as bends and straight lengths restrict the fl ue system and have a Flue Equivalent
Length (
FEL)
which must be added together to determine the total. Referring to the table below,
select a suit-
able fl ue system for the particular installation requirement and then calculate the
FEL
of the system, this must
not be greater than that stated above. Note: The FEL values below are typical values. Always check with the
fl ue supplier for exact values.
FLUE PARTS
80 / 125mm
F.E.L
(C13, C33 TYPE)
1.0 m Concentric Length
1.0 m
0.5 m Concentric Length
0.5 m
Concentric 90° Bend
1.2 m
Concentric 45° Bend
0.8 m
Vertical Terminal kit
1.6 m
Horizontal Terminal kit
1.0 m
Flue Condense Trap
1.5 m
Terminal Guard
N/A
Wall Clamp 125mm
Example C
33
:
A fl ue system that uses six straight lengths, three
90° bends and a horizontal terminal.
6 x 1m straight lengths
6.0 m
3 x 90° bends
3.6 m
1 x Horizontal Terminal
1.0 m
Total
(within 18m limit)
10.6 m
Use of support clamps to secure the fl ue sections to a solid structure :
Vertical sections should be secured using a clamp every 2.5 m
Horizontal sections should be secured using a clamp every 1.5 m
When the combustion fl ue system required is longer than 5.0m, it is recommended that a separate
system to capture excess condensation formed inside the fl ue is fi tted.
FLUE PARTS
80mm
F.E.L
(B23 TYPE)
1.0 m Length
1.0 m
0.5 m Length
0.5 m
90° Bend
4.0 m
45° Bend
2.0 m
Vertical Terminal kit
2.0 m
Horizontal Terminal kit
1.5 m
Flue Condense Trap
4.0 m
Terminal Guard
N/A
Wall Clamp 80mm
