10
FLUE INSTALLATION
The boiler is only suitable for top outlet flue con-
nection.
A - Flue to rear of boiler
• Mark correct position of hole from template.
B - Flue to side of boiler
• Mark the horizontal centre line for the hole on
the rear wall. Extend the horizontal centre line to
the side wall and mark the vertical centre line of
flue hole as shown in
diagram 9.
Under normal circumstances, it will be possible to
gain access to the outside of the building to fit the
flue terminal assembly. Where outside access is not
possible e.g. high rise buildings, the flue terminal
can be fitted from inside the building only if re-
quired.
Important:
When cutting the flue hole and when
extending 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.
Cutting the flue hole
• Making allowance for the slope of the flue, cut
hole in external wall, preferably using a core drill.
For installations with internal and external access
-
Use a 105 mm diameter core drill.
For installations with internal access only
- Use a
125 mm diameter core drill.
Important:
Before cutting the hole for flues to the
rear of boiler, always cover fixing jig to make sure it
is not damaged.
Calculation of flue cutting lengths
• Measure wall thickness
e
(mm),
see
diagram 9.
• For side flues, measure distance from inside face
of side wall to centre line of flue and subtract 260
mm for right and left hand flue to get dimension
a
(mm).
• Refer to
table 1
for cutting lengths of both inner
and outer flue pipes for each of the various flue
options available.
Important:
All flue cutting lengths must be meas-
ured from the terminal end of the flue pipes,
see
diagram 10
.
When the dimension
X
measured on site is greater
than that given in
table 1,
a flue extension kit will
be required, refer to
table 2
for details.
Diagram 9
Flue option
Dimension "X"
N
°
of
extension kits
Side flue
522 to 1478 mm
1
left or right
1479 to 2479 mm
2
Table 2
e
e
a
a
X
X
∆
L1
∆
L2
∆
L1
∆
L2
Flue option
Cutting length (mm)
Comments
outer pipe
inner pipe
Rear flue
e + 145
e + 228
maximum wall
thickness "e" without
extension 522 mm
Side flue left e + a + 188
e + a + 271
maximum
distance "X" without
extension 739 mm
Side flue right e + a + 188
e + a + 271
maximum
distance "X" without
extension 739 mm
Table 1
Diagram 10
Cutting length
Outer pipe
Inner pipe
Cutting length
Terminal end
V
en 089
