21
C4 Installing the Internal Vertical Powerflue
The internal vertical flue option is designed to have the box containing the fan
and electricals mounted within the roof space of the house, and the vertical
200mm diameter twin wall flue penetrate through the roof. The standard kit
comes with 1.2m of twin wall flue (post fan). Note total combined maximum
vertical flue before the fan must be less than 12metres (max 4m Flexi+ max 8m
polypro).
Use standard methods to flash the roof penetration, the installation must be
weather proof and conform to all local council standards including powered flue
roof termination rules.
The cowl surround should be fixed in place as shown
Mount the fan assembly box to roof framing using timber or builders strapping,
ensuring the flue is vertical and rigidly mounted.
Aim to have the fan box mounted as high as possible, mainly to allow sucient
fall for condensation drainage if the flexi-flue is to run horizontally.
Ensure there is sucient space below fan box to have access to fit the flexi-flue
tubes and to allow flowing bends if required.
Note: The vertical powerflue and the flexi flue connections must be installed
in a location accessible for service or replacement, a service hatch or
removable flashing to allow for access may be required.