Potterton Promax 15 HE Installation & Service Instructions Manual page 22

Wall Thickness
3°
(1 in 20)
Fig. 26
Waste
Fig. 27
22
360° Orientation
(Z) Edge of Wall Plate to Wall
Wall Thickness
(Z) = Side Exit
(X) = Rear Exit
Flue
Inner Flue Support Bracket
Fig. 27a
8.0 INSTALLATION
8.6 Making the Gas Connection
1. Connect the gas supply to the RC
internal) gas tap located on the lower right side of
the boiler.
8.7 Fitting The Flue
Before fitting the flue, check the condensate
drain integrity (see section 8.5).
IMPORTANT: The flue should always be installed
with a 3° (1 in 20) fall from terminal to elbow, to
allow condensate to run back to the boiler.
HORIZONTAL FLUE
1. The standard flue is suitable for lengths 270mm
minimum to 800mm maximum (measured from the
edge of the flue elbow outlet).
Rear Flue: maximum wall thickness - 630mm
Side Flue: maximum wall thickness - 565mm (left or right)
2. For rear exit - measure the wall thickness
(Fig. 26) and to this dimension add 210mm. This
dimension to be known as (X).
i.e.
(X) = wall thickness + 210
3. Take the flue and mark off (X) from the terminal
end as indicated in the diagram
(Fig. 27).
Check your dimensions.
The flue tubes are fixed together. Cut through both
tubes whilst resting the flue on the semi-circular
packing pieces. Deburr both tube ends.
4. For side exit - measure the distance from the
edge of the wall plate to the inner face of the wall
(Fig. 26) and to this dimension add the wall
thickness + 250mm. This dimension to be known as
(Z).
i.e.
(Z) = wall plate to wall + wall thickness + 250
5. Take the flue and mark off (Z) from the terminal
end as indicated (Fig. 27).
Check your dimensions.
The flue tubes are fixed together. Cut through both
tubes whilst resting the flue on the semi-circular
packing pieces. Deburr both tube ends.
IMPORTANT: Check all measurements before
cutting.
NOTE: When cutting ensure the cut does not
interfere with the inner flue support bracket
(Fig. 27a).
Publication No. 5106451
1 / ( 1 / in BSPT
2 2