Baxi Megaflo System HE IE Series Installation & Servicing Instructions Manual page 25

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Vertical Flues
IMPORTANT: All flue systems must be securely supported at least
once every metre. Suitable pipe supports are available as accessories.
Vertical Flues (Twin Pipe)
Total Equivalent Length = A+B+C+1x90°Bend
All vertical and angled runs must be included, measured from the boiler adaptor
(point i) to the joint with the flue terminal
(point ii). One 91.5° bend or two 135° bends can be included without reduction of the flue length.
If further elbows are required the flue length must be reduced by the following amounts:-
1 metre for each 91.5° bend
0.5 metre for each 45° bend