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Installation and maintenance instructions 0020244997_07
▶
If you cannot guarantee that the materials from which the
condensate discharge pipe is made are suitable, install a
system to neutralise the condensate.
▶
Connect the condensate discharge
(1)
to a condensate
discharge pipe
(3)
that has a minimum internal diameter
of 19 mm (30 mm internal diameter for all external pipes
that are fed out of the building) and is made from an acid-
resistant material (e.g. plastic overflow pipe).
–
The condensate discharge pipework must have
a continuous fall (45 mm per metre) and should
whenever possible terminate at a suitable discharge
point within the heated envelope of the building
that will remain frost free under long periods of low
external temperatures.
Note
Ensure that the connection between the con-
densate discharge pipe and the drain hose is
not air-tight.
▶
During installation remove all burs from inside of cut pipe
work and avoid excessive adhesive which may trap small
pockets of water close to the pipe wall which can freeze
and build into a larger ice plug.
▶
As with other pipe work insulate the condensate dis-
charge pipe to minimise any risk of freezing and beware
when crossing cavities that the fall is maintained and the
pipe sleeved.
▶
Ensure that the condensate discharge pipe terminates in
a suitable location. Further information can be obtained
from BS 6798 Specification for installation of gas
–
fired
boilers of rated input not exceeding 70 kW net.
▶
Leave an installation space of at least 180 mm beneath
the condensate trap.
7.10.1 Condensate discharge systems
The condensate is discharged periodically in ‘slugs’ by si-
phonic action. It is not necessary to provide extra traps in the
discharge pipe as there is already a trap inside the boiler.
Fitting an extra trap may cause the boiler siphon to work in-
correctly. Refer to BS5546 or BS6798 for further advice on
disposal of boiler condensate.
7.10.1.1 Direct Connection to internal soil and vent
stack
Ø22mm
Preferred option
7.10.1.2 Direct connection to external soil and vent
stack
Ø22mm
Ø 32mm
≤ 3 m
7.10.1.3 External termination to gulley or hopper
Ø22mm
Ø 32mm
≤ 3 m
Best practice
7.10.1.4 Internal termination into combined sink
waste
Ø32mm
Ø22mm
≥ 3 m
100mm
Preferred option for external termination
