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REAR OUTLET FLUE INSTALLATION
For installations with internal and external access For installations with internal access only Important: Before cutting the hole for flues to therear of boiler, always cover fixing jig to make sure it
is not damaged. diagram 12.Important: - Use a125 mm diameter core drill. -Use a 105 mm diameter core drill. Cutting the flue hole a (mm), seediagram 13 Important: B-Rear outlet side flue •Making allowance for the slope of the flue, cut
hole in external wall, preferably using a core drill. Calculation of flue cutting lengths All flue cutting lengths must be meas-ured from the terminal end of the flue pipes, When cutting the flue hole and whenextending the flue centre line to a side wall, remem-
ber that the flue system must have a fall of about
35 mm per metre of flue DOWNWARD AWAY FROM
the boiler. There must NEVER be a downward in-
cline towards the boiler. or 14. •Refer to Mark the horizontal centre line on the rear wall.
Extend the horizontal centre line to the side wall
and mark the vertical centre line of the flue hole
as shown in •Measure wall thickness table 1 for cutting lengths of both innerand outer flue pipes for each of the various flue
options available. e (mm).•For side flues, measure distance from inside face
of side wall to centre line of flue and subtract 176
mm for right hand flue or subtract 234
for left hand flue to get dimension seediagram 15 .When the dimension X measured on site is greaterthan that given in
255 mini table 1, a flue extension kit willbe required, refer to table 2 for details.Refer to table 1 for the cutting lengths of both theinner and outer pipes for each of the flue optionsavailable.
234
60
50mini29 Diagram 12 Ins 012a ea X Diagram 13 Hab 208 Table 1Flue cutting lengths Cutting length (mm)Flue optionouter pipeinner pipeComments Rear outlete + a + 96e + a + 173maximumSide flue todistance 'X'
leftwithout
(Diagram 13)extension1080 mm Rear outlete + a + 154e + a +231maximum
Side flue todistance 'x'
rightwithout
(Diagram 14)extension 1080 mm ea X
Diagram 14 Hab 209 11