andrews COMBIflo 100/300, Инструкция по установке, эксплуатации и обслуживанию

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ANDREWS COMBIfl o 21 GB
4.4 NEW AND EXISTING HEATING SYSTEMS
Whether connecting to an existing or a new heating system, a fi lter/strainer (with two isolation
valves)
must be fi tted in the return pipe. When necessary it can be removed and cleaned, which will
help protect the appliance from contaminants, from within the heating system.
4.4.1 EXISTING SYSTEMS
Before replacement of an existing boiler, it is necessary to thoroughly clean out the old system fi rst. This is best
achieved by introducing a basic cleaning solution up to 4 weeks before the substitution.
When the appliance is installed on existing systems, please ensure you have considered the following before
commissioning:
• If you intend to use the existing fl ue on a B23 category system, check that fl ue outlet is suitable for
condensing boilers, is the correct size, is correct for the temperature of the products of combustion and
is manufactured according to current regulations. It must be tested for soundness and must not have
any restrictions or defects. Also ensure that the fl ue outlet pipe has a connection for the discharge of
condensate. For all other fl ue types, it is recommended that a completely new fl ue system is installed.
• The boiler room has a suitable outlet for the discharge of condensate produced.
• The electrical connections comply with the current electrical standards and the work has been com-
pleted by a suitably qualifi ed person.
• The gas supply pipe work is constructed to the current regulations in force.
• The expansion vessels and associated fi ttings are correctly sized to absorb the total expansion of the
system and is in tested working order.
• The circulation pump’s output, the head and fl ow direction are suitable for the system.
• The complete system has been cleaned of impurities and lime scale.
4.4.2 NEW SYSTEMS & WATER QUALITY
It is recommended to thoroughly clean out the new system with a system fl ush product, before commission-
ing the appliance. It is essential, for the long life of the appliance that the following water quality limits are not
exceeded:
If the system contains aluminium parts, the pH level must be less than 8.5. The pH value inside the
system should only be measured after a steady state has been achieved (i.e. all fi lling and bleeding
operations have been completed)
CAUTION
Chloride values of the system water and the supply water should be compared at regular intervals.
If the Chloride value of the system water is considerably higher than the supply value, this would
indicate that there is system leakage and water is being lost to evaporation. This will result in Chlo-
ride concentration and premature boiler failure if left untreated. If Chloride concentration levels have
exceeded 200mg/l, the system should be fl ushed clean and refi lled with low Chloride water and
appropriate system treatments.
Water Hardness < 250ppm
Chlorides < 200mg/l
Acidity 7.5 to 9.5 pH
Iron < 0.5 mg/l
Copper < 0.1 mg/l