38
FITTING AIR/FLUE DUCT EXTENSIONS
How to add extensions
Use a saw, tin-snips, etc. to cut tubes
to size.
☞
No tools are required when
removing previously-fitted
extensions for cutting to size air
and flue tubes separately. When
doing so, the flue conduit should
be twisted into a position where
the shoulders on the plastic tube
can be pushed through the spacer-
piece. After cutting to size, refit
the flue conduit and secure it to
the air conduit.
Tip:
Start by measuring the required
length of air conduit* (Lair), and then
calculate the corresponding length of
flue conduit (Lexhaust) as follows:
Lexhaust = Lair + 40 mm
Lexhaust = length of flue conduit
Lair
= length of air conduit
* Minimum length of air-conduit
extension: 100 mm.
1
2
15
1
2
70
L air
Lexhaust
1.
2.
+ 40 mm
25
Fig. 10.1: Cutting tubes to size
☞
The seals are sensitive to mineral
oil-based grease products. For this
reason, the seals must not be
greased. If the seals need wetting
to aid in installation, use water
only.
☞
De-burr and file down any rough
edges on the tubes before fitting in
order to prevent damage to the
seals. Remove all metal filings and
other debris.
☞
Do not use damaged or dented
tubes, as they will not form an
adequate seal.
☞
Ensure that the seals remain
correctly aligned when installing
the tubes. Do not fit damaged
seals.
☞
Secure the exhaust conduit with
the fixing device in order to ensure
that it is correctly centred relative
to the air conduit.
Fig. 10.2: Loosening the flue conduit
GU_LAZ 290/1
