7.0 Site Requirement
21
© Baxi Heating UK Limited 2005
Key
Accessory
Size
Baxi Code
Number
Concentric Flue System 110mm diameter
A
Horizontal flue kit
850mm
236921
B
Straight extension kit
1000mm
241695
500mm
241694
250mm
241692
C
Bend kit
93°
241687
D
Bend kit (pair)
45°
241689
E
Horizontal flue terminal
243013BAX
Clamp
110mm
243014BAX
Twin Flue System 80mm diameter
F
Straight extension kit
1000mm
238690
500mm
238692
250mm
238694
G
Bend kit
90°
246139
H
Bend kit (pair)
45°
246138
Universal Vertical Flue Kits
J
Twin flue adaptor kit
242757
K
Vertical flue terminal
242802
L
Universal roof tile
25°/50°
243015
M
Roof cover plate kit
243131
N
Flat roof flashing
243016BAX
R
Boiler connection vertical concentric
242886
Clamp
80mm
238684
7.10
Flue options
Concentric
The maximum equivalent lengths are 4m (horizontal) or
5m (vertical). There lengths exclude the standard elbow
and flue/terminal assembly (horizontal) and terminal
assembly (vertical).
Twin Flue
The total maximum equivalent flue length is 40m.
NOTE:
Each 1m of flue duct should be calculated as 2m.
Any additional “in line” bends in the flue system must be
taken into consideration. Their equivalent lengths are:
Concentric Pipes:
45º bend
0.5 m
93º bend
1.0 m
Twin Flue Pipe:
45º bend (air duct)
1.3 m
45º bend (flue duct)
2.6 m
90º bend (air duct)
4.8 m
90º bend (flue duct)
9.6 m
Detailed examples of equivalent flue length calculation are
given in the Installation Guidance Notes for each flue
system type.
(Documents 243501 and 243502 for concentric and twin
pipe respectively).
A - Standard Flue
D
C
B
E
K
L
M
D
J
F
J
N
H
G
R
Plume Displacement
70/110 dia Kit