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Alpha CD90S/115S - General Boiler Information
3.11 DISPOSAL OF CONDENSATE
Provision must be made for the safe disposal of condensate produced by the flue gases of the Alpha CD90S or CD115S
boilers and reference should be made to BS 6644 for the requirements on the disposal of condensate.
The boilers incorporate a condensate trap, therefore no additional trap is required.
The condensate should ideally be discharged internally into an internal waste pipe or soil pipe to avoid the possible risk of
freezing. The pipework must be in 22 mm pipe.
External pipe runs should be avoided, but if it is necessary, the pipework should be at least 32 mm and protected from
the risk of freezing with a waterproof insulation and the length should be kept to a maximum of 3 m. Termination should
be into an external gulley or soakaway as shown in Figs. 10 and 11.
Note:
All pipework must have a continuous fall (see Figs. 10 and 11) from the boiler and must be of an acid resistant
material such as plastic waste pipe. (copper or steel is not suitable).
It should be noted that the connection of a condensate pipe to a drain may be subject to local building control requirements.
Fig. 11 - External soakaway
Ground level (either/or)
22mm termination
from boiler
2½ fall
O
25mm
300mm
Two rows of 3 x 12mm
holes at 25mm centres,
50mm from the bottom
of the tube. Holes to face
away from house.
Cement mortar
sealing
100mm plastic tube
Bottom of tube sealed
Soakaway depth 400mm
filled with limestone chippings
500 mm min.
Fig. 10 - External gully
Open end of pipe
diverted into gully
below grid but above
water level
Use waterproof
pipework insulation
in very exposed
positions
Ensure pipe is
adequately supported
Plastic pipe
Minimum gradient 2½°
