Vaillant ecoTEC sustain 24 Installation And Maintenance Instructions Manual page 20

Note
The condensate drain pipework must have a
continuous fall (45 mm per metre) and should
whenever possible terminate at a suitable
drain 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.
▶
Connect the condensate siphon (1). Use the supplied
condensate discharge hose (2) to do this.
▶
Connect a condensate discharge pipe (21.5 mm, not in-
cluded in the scope of delivery) to the condensate dis-
charge hose (2).
▶
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.
You can find further information in the "BS 6798" specific-
ation for installing and maintaining gas-fired boilers with a
nominal heat input of less than 70 kW.
7.8.1 Condensate discharge systems
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 incorrectly.
Refer to BS5546 or BS6798 for further advice on disposal of
boiler condensate.
7.8.1.1 Direct Connection to internal soil and vent
stack
Preferred option
20
Ø22mm
Installation and maintenance instructions ecoTEC sustain 0020253094_05
7.8.1.2 Direct connection to external soil and vent
stack
≤ 3 m
7.8.1.3 External termination to gulley or hopper
≤ 3 m
Best practice
7.8.1.4 Internal termination into combined sink
waste
≥ 3 m
Preferred option for external termination
Ø22mm
Ø 32mm
Ø22mm
Ø 32mm
100mm
Ø22mm
Ø32mm