Installation In Older Systems And Systems Requiring Modernisation; Central Heating System Water Quality Requirements - Beretta Novella MAXIMA 129 N RAI Installation Manual

2.11
Installation in older systems
and systems requiring mod-
ernisation
When installing Novella MAXIMA boilers in
older systems or systems requiring moderni-
sation, always perform the following checks.
- Make sure that the flue is able to withstand
the temperature of the combustion gases
and that it has been designed and made
in compliance with applicable standards.
The flue must also be as straight as possi-
ble, sealed, insulated and not blocked or
choked.
- Make sure that the electrical supply system
has been installed by a qualified electrician
in compliance with applicable standards.
- Make sure that the fuel supply line and
fuel storage tank (if present) are made
and installed in compliance with applicable
standards.
- Make sure that expansion vessel is big
enough to contain the additional volume
16
generated by thermal expansion.
- Make sure that flow rate, head and direction
of flow of the circulation pumps are suitable
and correct.
- Make sure that the central heating circuit has
been flushed out to remove all sludge and
lime scale, and that it has been bled and
seal tested.
b
The manufacturer declines all responsi-
bility for damage caused by incorrectly
constructed flue systems.
2.12
Central heating system water
quality requirements
If your Novella MAXIMA boiler is to be
installed in an older system or a system
requiring modernisation, make sure that a
suitable water treatment system is installed
if the quality of the supply/recirculation water
so demands. (Refer to the values listed in the
table.)
REFERENCE VALUES
pH
Electrical conductivity
Chlorine ions
Sulphuric acid ions
Total iron
Alkalinity M
Total hardness
Sulphur ions
Ammonia ions
Silicon ions
a
It is forbidden to fill or top up the central
heating circuit while the boiler is func-
tioning. Doing so may cause serious
damage to the boiler.
6-8
less than 200 mV/cm (25°C)
less than 50 ppm
less than 50 ppm
less than 0.3 ppm
less than 50 ppm
less than 35°F
none
none
less than 30 ppm