Bosch WORCESTER Greenstar CDi Classic Series Technical Information page 39

External connections
Freezing conditions
•
When the position of the boiler prevents internal
routing, we recommend installing a Worcester
CondenseSure siphon to minimise the risk of freezing
•
Pipework length should be kept to a minimum and the
route as vertical as possible
•
Weather-proofi ng insulation must be sized when not
using a CondenseSure siphon.
Condensate waste
•
Care should be taken when siting a soak away to avoid
obstructing existing services.
If no other discharge method is possible, then the use of
an externally-run condensate drainage pipe terminating at
a suitable foul water discharge point (fi g. 4), or purpose-
designed soak away (fi g. 5), may be considered. Please see
installation and servicing instructions for more details.
Insulate
& increase
pipe size
Siphon
trap
Pipework
transition
43mm 90º
male/female
bend
Fig. 4 Disposal into a rainwater down pipe
Siphon
trap
Pipework
transition
Fig. 5 External disposal
For full technical information on pipe size, insulation
and different condensate pipework methods, please
see Installation, Commissioning and Servicing
Instruction Manual.
External
rain water
pipe into
foul water
External
air break
Air gap
68mm dia. PVCu
strap on fitting
Insulate
& increase
pipe size
25mm min.
Condensate soak away (see fig. 6)
•
The condensate drainage pipe may be run above or below
the ground to the soak away
•
The examples shown run above ground
•
The soak away must use a 100mm dia. plastic tube with
two rows of three 12mm holes on 25mm centres and
50mm from the bottom of the tube. The holes must face
away from the house
•
The tube must be surrounded by at least 100mm of
limestone chippings to a depth of 400mm
•
Minimum hole size for the condensate soak away must be
400mm deep by 300mm dia.
In situations where there are likely to be extremes of
temperature or exposure, the use of a proprietary trace
heating system for external pipework (that incorporates
an external frost thermostat) should be considered. If
such a system is used, the requirement to use 32mm pipe
does not apply, however all other guidance above, and the
instructions for the trace heating system, should be
closely followed.
Unheated internal areas
Internal pipe runs in unheated areas such as lofts,
basements and garages should be treated as external runs,
with consideration given to using a CondenseSure siphon.
Siphon
trap
500mm min.
Insulate
& increase
pipe size
Pipework
transition
100mm
dia. min.
plastic
pipe
Limestone chippings
Fig. 6 Soak away
In addition to the condensate discharge options illustrated
on these pages and in the Installation, Commissioning
and Servicing Instruction Manual, the new Worcester
CondenseSure siphon provides an innovative alternative
for the prevention of freezing for externally run discharge
condensate (see over for details).
100mm
dia. min.
100mm dia.
plastic pipe
Drainage
holes
300mm
12mm dia.
25mm
25mm
50mm
25mm
25mm min.
400mm
Drainage min.
holes
Bottom of sealed tube
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