Adveco AGUADENS 210T, Инструкция по установке, использованию и техническому обслуживанию

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35
60T - 280T
COSMOGAS
10.5 - Connection of expansion tank
WARNING! The boiler has no expansion
tank. Provide the system with an expansion tank
of a suitable size, as laid out in national and local
installation regulations.
10.6 - Delivery and return
WARNING! COSMOGAS is not liable for any
damage caused by incorrect use of additives in the
central heating system.
WARNING! The system after the appliance
must be made with materials that resist temperatures
up to 97°C and pressure of 11 bar. Otherwise (e.g.
with plastic piping), the system must be fitted with the
relevant protection and safety devices.
Before connecting the plumbing, wash the system
thoroughly to eliminate any waste (hemp, radiators casting
sand, etc.), which could damage the appliance. This must
also be performed if the appliance is replaced.
In figures 8-1 and 8-2 you can check the positioning of the
delivery and return connections.

Install a metal mesh filter on the return pipe with passage
of 1 mm
2
in order to trap any system residues before they
return to the boiler.

Do not use the appliance to introduce any type of
additive into the system.
10.7 - MYDENS boiler water supply
WARNING! The connection of the system
(and therefore the boiler) to the water mains must be
completed with the insertion between them of a device
that prevents backflows to the drinking water system,
as required by the anti-pollution safety regulations in
force.
10.7.1 - Recommendations on
characteristics of water in the system
Filling the central heating system is an extremely delicate
operation that should not be underestimated, either in cases
of just replacing the heat generator or in when a new appliance
is installed. Incorrect assessment of the characteristics of the
system’s water can lead, in some cases, to damage to the
system and heating unit. A system is almost never perfectly
sealed; sometimes there may be water leaks and oxygen can
also get in; both these phenomena cause damage.
Among the parameters that can have a negative impact on the
lifetime of a system, the following are the main ones:
- The simultaneous presence of different metals (copper, brass,
steel and aluminium) which, in an aqueous environment, give
rise to galvanic corrosion.
- The presence of free oxygen, due to air infiltration which may
occur near to joints or seals, constitutes a typical corrosive
agent, particularly active at temperatures between 50 and
70° C.
- Water leakage, which leads to frequent refills, can cause
corrosion or limescale, depending on the type of water
available for the fillings. In all cases all of the leaks (and
relative refills) must be kept under control, especially when an
automatic filling system is installed. In this case it is definitely
recommended that a meter be installed which can indicate
the quantity of water replenished.
Natural or added impurities in the water. A lot of drinking
water can contain concentrations, which may be significant,
of chlorides and sulphates that can increase the speed of
corrosion of metallic surfaces. Other undesirable components
could have been introduced into the system before or during
installation (building materials, metallic chips, shavings,
grease, deposits and dirt in general). Residues from welding
can also cause corrosion, both in new systems and after
modifications and repairs. In old systems planned to work
with radiators, characterised by pipework with a very large
diameter, the water content of the system is significant and
fosters the formation of dirt and deposits.
Dirt and Limescale The presence of black deposits (magnetite)
indicates that there is limited corrosion, however, the high
specific weight of this oxide can cause blockages that are hard
to remove, especially in the hottest areas. Limescale is due to
the hardness of the water, or to the presence of calcium and
magnesium salts. Calcium, in the form of calcium carbonate,
is deposited in the hottest areas of the system. Magnetite often
contributes to consolidating the limescale. On the other hand,
iron oxide (the water has a reddish colour) is an indicator of
corrosion from oxygen.
Frequent leaks. Where there are frequent leaks the hydrogen
and/or air accumulate on the top part of the heat exchanger
and radiators, preventing full exchange of heat. When the
electrolytic corrosion process has begun, the water level in
the system is lowered, gases accumulate in the top part of the
heat exchanger and radiators. The presence of air is caused
by the fact that the system might not be perfectly sealed. A
slow drop in system pressure due to a leak is often difficult to
find, especially when the leak is minimal (in winter leaks from
radiator valves sometimes are not visible because they are
dried by the heat produced by the radiator or boiler). These
micro-leaks do, however, allow air to get into the system.
The main points that micro-leaks can develop are at the
joints and, in particular, on the intake side of the pump (air
vent valve, seals with O-rings, fill valves). In these cases, to
avoid damage, the system must be protected with a suitable
corrosion inhibitor.
10.7.2 - For correct operation of the
system make sure that:
1) the system has no leaks or at least the most obvious leaks
have been repaired;
2) if there is an automatic filling system, a litre counter must
have been installed so as to know the exact quantity of any
leaks;
3) filling the system and refilling is done with softened water
so as to reduce its overall hardness. The water must also be
conditioned in order to keep the pH within the threshold set
so as to avoid corrosion;
4) Both on new systems and system replacements there must
be efficient systems to get rid of air and impurities; filters,
micro-impurity separators and micro air bubble separators;
5) Avoid discharging water from the system during normal
maintenance operations, even if it is apparently insignificant
quantities: for example when cleaning filters, equip the system
with the relevant isolation valves up and down stream from
the filter itself;
6) Always carry out an analysis of the system water before
opening communication between a new boiler and the system,
to establish whether the chemical and physical properties of
the water indicate the need to carry out complete emptying
of the system, the use of the water already in the system
or chemical washing of the system, using mains water with
the addition of a detergent, when there is a suspicion that
10 - INSTALLATION - Plumbing connections - MYDENS boiler