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Antifreeze protection of the system by adding antifreeze liquid.
Protect the central heating circuit from freezing by
inserting a good-quality antifreeze liquid into this
circuit, which is specially suited for central heating
systems and which is manufacturer guaranteed not
to cause damage to the heat exchanger or other com-
ponents of the units.
The antifreeze liquid must not be harmful to one’s health.
The materials used for the central heating circuit of Immergas
units resist ethylene and glycol based antifreeze liquids (if the
mixtures are prepared perfectly). Adding glycol lowers the
freezing point of water.
The required concentration depends on the lowest expected
external temperature and if bursting or freezing risks on the
system must be prevented. More glycol is required to prevent
the system from freezing. Add glycol according to the indica-
tions of the table below.
An aqueous solution must be made with potential pollution
class of water 2 (EN 1717:2002).
For life and possible disposal, follow the supplier’s instructions.
INFORMATION
- Protection from risk of bursting: glycol prevents the
pipes from bursting, but it does NOT prevent freezing
of the liquid they contain.
- Protection from risk of freezing : glycol prevents freezing of
the liquid contained inside the pipes.
Lowest
expected
external tem-
perature
Prevention from
risk of bursting
Prevention from
risk of freezing
–5°C
10%
15%
–10°C
15%
25%
–15°C
20%
35%
–20°C
25%
—
–25°C
30%
—
NOTE
- The required concentration may vary according
to the type of glycol. ALWAYS compare the requi-
rements of the table above with the specifications
provided by the glycol manufacturer. If necessary,
comply with the requirements provided by the glycol
manufacturer.
- The concentration of additional glycol must NEVER exceed
35%.
- If the liquid in the system should feeze, the pump will NOT
be able to start. Remember that the risk of freezing of the
liquid in the system is present if even if the bursting risk of
the system is prevented.
ATTENTION:
The presence of glycol may trigger
corrosion of the system, since glycol
without inhibitors becomes acid under the
influence of oxygen. The process is accele-
rated by the presence of copper and high
temperatures. Non-inhibited acid glycol
affects metallic surfaces and creates galvanic
corrosion cells that cause serious damage to
the system.
Therefore, it is important that:
- a proper water treatment is performed by a
specialised technician,
- a glycol with corrosion inhibitors able to
contrast the acids formed by glycol oxidation
is selected,
- car glycol is not used, since its corrosion
inhibitor has a limited duration and contains
silicates which may obstruct or clog the sy-
stem,
- galvanised pipes are NOT used in systems
with glycol, since their presence may cause
some components in the inhibitor to be cor-
roded by glycol.
If the hydraulic circuit contains glycol, the corre-
sponding function must be enabled (see Par 3.6).
