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7.0
SITE REQUIREMENTS
20
Publication No. 5111817
7.11
Flue Options
1. The Potterton Performa System HE range can be
fitted with flue systems as illustrated.
2. The standard flue is suitable only for horizontal
applications.
3. Maximum permissible equivalent flue lengths
are:-
12,18
24
28
Concentric
5m
4m
3m
Vertical
5m
4m
3m
Vertical Twin Pipe
15m
12m
12m
4. Any additional “in line” bends in the flue system
must be taken into consideration.
Their equivalent lengths are:-
Concentric Pipes:
45° bend
0.5 metres
93° bend
1.0 metres
Twin Flue Pipe
45° bend
0.25 metres
91.5° bend
0.50 metres
The elbow supplied with the standard horizontal flue
is not included in any equivalent length calculations
5. The illustrations opposite show examples of
maximum equivalent lengths.
6. Instructions for guidance and fitting are included
in each kit where appropriate.
NOTE:
Flue length is measured from point A to B
as shown.
Horizontal
Flues
Vertical
Flues
Vertical
Flues
(Twin Pipe)
B
A
B
A
B
A