15
Fig. 4.7 - 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 32 mm)
Minimum gradient 2½°
4.9 FLUSHING THE HEATING SYSTEM
It is essential that the central heating system is thoroughly cleaned and flushed before fitting an Alpha E-Tec
Plus boiler. Failure to do so will invalidate the warranty. The primary condensing heat exchanger is constructed in
stainless steel and therefore is compatible with most materials used in a heating system.
Where possible, the heating system should be cleaned before installing the boiler. A proprietary cleaner should
be used following the product manufacturers' instructions. After installation the system should then be filled and
flushed before final filling. A corrosion inhibitor approved by Alpha must be added to ensure that the heating system
operates effectively and efficiently, it is important to maintain the correct level of corrosion inhibition at all times.
The corrosion inhibitor should be checked annually at the time of the boiler service, and topped up if necessary. A further
dose of corrosion inhibitor should be added to the system every five years.
It is important to ensure that the correct level of inhibitor has been added, and that any cleaner residues have been
adequately removed to maintain the operation of the boiler and heating system. Failure to correctly clean and treat the
system will invalidate the boiler warranty.
If it is not possible to clean the system before fitting the new boiler, the system should be cleaned using a proprietary cleaner
and a magnetic filter connected in the return before the boiler as this is the most effective method of ensuring that any
magnetite and rust particles are prevented from entering and damaging the boiler.
Once the system condition has been restored, an effective magnetic filter and strainer should be fitted permanently to the
system as a method of collecting any magnetite and rust from the system during operation.
4.10 DISPOSAL OF CONDENSATE
Provision must be made for the safe disposal of condensate produced by the flue gases of the Alpha boilers and
reference should be made to BS 6798 for the requirements on the disposal of condensate.
The boilers incorporate a condensate trap which has a seal of greater than 75 mm, therefore no additional trap is required.
The condensate should ideally be discharged internally into an internal waste pipe (washing machine/sink waste) or soil pipe
to avoid the possible risk of freezing. The pipework must be in 22 mm pipe (minimum).
External pipe runs should be avoided, but if it is necessary, the pipework should be protected from the risk of freezing with
waterproof insulation and the length should be kept to a maximum of 3 m and the condensate pipework should be increased
to a minimum of 32 mm diameter. Termination should be into an external gulley or soakaway as shown in Figs. 4.7 and 4.8.
Note:
All pipework must have a continuous fall (see Figs. 4.7 and 4.8) from the boiler and must be of an acid resistant
material such as plastic waste pipe. (copper or steel is not suitable).
The condensate pipe is combined with the expansion relief discharge. The flexible condensate hose supplied meets the
requirements for use with both condensate and expansion relief. This should be connected to a suitable waste pipe and
fittings with approval for hot and cold water, i.e. BS EN1451-1PP Waste piping, BS EN1455-1 ABS piping or BS EN 1566-1
MUPVC piping.
The condensate and discharge should be connected to a drain for sewage and foul waste or a dedicated soak away with
neutraliser added.
It should be noted that the connection of a condensate pipe to a drain may be subject to local building control requirements.
Alpha Evoke 28 and 33 - General Boiler Information
