Technical data

For full technical information on pipe size, insulation
and different condensate pipework methods, please
see Installation, Commissioning and Servicing
Instruction Manual.
All condensing boilers generate condensate discharge
which needs to be piped away from the appliance using a
plastic pipe.
The amount of condensate generated depends on the
efficiency and operating status of the appliance. Depending
on operating temperatures, the appliance will condense in
both heating and hot water modes and may generate up
to 2.7 litres of condensate per hour for the 440CDi and
3.7 litres per hour for the 550CDi Regular.
Condensate termination and route
Greenstar Highflow CDi combi boilers incorporate a
condensate pump which allows condensate to be plumbed
above the boiler, allowing more flexible siting possibilities.
Condensate connection
The condensate pump fills up and periodically discharges
through the flexible condensate pipe between 200mm and
4,500mm from floor level. After this point the condensate
continues down the 22mm rigid pipework to the outlet
using gravity.
•
The flexible plastic pipe can be reduced in length to suit
the installation circumstances. The pipework must follow
one of the options shown opposite.
Never terminate or discharge into any open source,
including: sink, bath, shower, bidet, toilet etc.
Note: any external condensate pipework should be
protected with weather resistant insulation to help
prevent freezing.
Condensate pipework
Max. 4,500mm
Cut off
excess
pipework
Min. 200mm
Condensate pump
22
The condensate connection on Worcester appliances is in
22mm polypropylene. The pipe should be extended and run
away from the appliance with a constant fall of 3º or
at least 50mm in every metre away from the boiler.
The condensate pipe can terminate into any one of
four areas.
Whilst all of the methods are acceptable it is best practise
to terminate the condensate pipe via an internal waste
system. This will eliminate the need for any external
condensate pipe runs which can be susceptible to freezing
in extreme weather. Best practise is not to run external
condensate pipe any further than 3m. If it is necessary to
run more than 3m externally increase pipe size to 32mm.
Condensate termination and route
External condensate pipework
The Worcester Greenstar Highflow CDi combi appliances
have a condensate pump rather than a siphonic condensate
trap. Rather than the condensate constantly dripping into
the discharge pipe, the condensate is collected in the pump
which releases it in 100ml quantities. This will help prevent
freezing occurring.
Wherever possible the condensate discharge pipework
should be routed and terminated internally. Should this not
be possible, and the only available route is external, the
following conditions should be observed:
•
The pipework length should be kept to a minimum and
the route as vertical as possible
•
Where pipework could be subjected to extreme cold
or wind chill, a weather proof insulation should be
used. Alternatively, the condensate pipework could be
increased to a minimum 32mm.