Beretta 20141085, Installation Manual

Page: 34 / 112

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2.10 Neutralization of the condensate
To correctly eliminate the combustion condensate, check if the con-
densate needs to be neutralized using a designated accessory.
- For systems with a nominal heat input greater than 200 kW, the
condensate always needs to be neutralized
- For systems with a nominal heat input greater than 35 kW but
less than 200 kW, the selection and evaluation criteria is pro-
vided in the figure below
0
1
2
3
4
5
6
7
8
9
10
0
10
20
30
40
50
60
70
80
90
100
Number of apartments Number of occupants
Generator power in kW
0 50 75 35 125 150 175 200 100
Neutralization not
required
Neutralization
required
Example 1
Example 2
Example 1
For a residential building with 4 apartments, a 75 kW condensing boil-
er needs to be installed. The 4 apartments / 75 kW intersection point
is within the range "neutralization not required", therefore the conden-
sate does not need to be neutralized.
Example 2
For an office block with 45 users, a 160 kW condensing boiler needs
to be installed. The 45 users / 160 kW intersection point is within the
range "neutralization required", therefore the condensate needs to be
neutralized.
In the case of residential applications, reference must be made to
the number of apartments served by the system, while in the case of
non-residential applications, reference must be made to the number
of users.
In the case of mixed applications, the number of apartments must
be converted into equivalent users, or conversely, according to the
alignment of the two vertical axes, therefore refer only to one axis (for
example, 2 apartments equate to 20 users).
b
The condensate drainage system must be sized and installed
to ensure correct elimination of the effluents produced by the
appliance and/or by the evacuation system of the combustion
products in any and all operating conditions.
2.10.1 Water quality requirements
It is ABSOLUTELY NECESSARY to treat the water system in order
for the heat generator to work properly and to guarantee its service
life, as well as that of all its components. This not only applies to jobs
carried out on existing installations but also on new installations.
Sludge, lime-scale and pollutants contained in the water can cause
permanent damage to the heat generator, also within a short time and
notwithstanding the quality standards of the materials used.
Contact the Technical Assistance Centre for any further information
on type and use of additives.
The heat transfer fluid (water) for the central heating circuit must con-
form to the quality parameters given in the following table:
Parameters Value Unit
General character-
istic
Colourless, without
sediment
PH value Min. 6.5; Max. 8 PH
Dissolved oxygen < 0,05 mg/l
Total iron (Fe) < 0,3 mg/l
Total copper (Cu) < 0,1 mg/l
Na2SO3 < 10 mg/l
N2H4 < 3 mg/l
PO4 < 15 mg/l
CaCO3 Min. 50 ; Max.150 ppm
Trisodium phosphate None ppm
Chlorine < 100 ppm
Electrical conduc-
tivity
<200 μS/cm
Pressure Min. 0.6; Max. 6 bar
Glycol
Max. 40% (only
propylene glycol)
%
b
All data in the table refer to water contained in the system after
8 weeks' operation.
b
Do not use excessively softened water. Excessive water sof-
tening (total hardness < 5° f) results in corrosion due to contact
with metal elements (pipes or thermal module components)
b
Immediately repair any leaks or drips that could result in air
entering the system
b
Excessive pressure fluctuations can cause stress and fatigue
to the heat exchanger. Keep the operating pressure constant.
b
Water used to fill a system for the first time and water used
to top it up must always be filtered (using synthetic or metal
mesh filters with a filtration rating of no less than 50 microns) to
prevent sludge from forming and triggering deposit corrosion.
b
If oxygen enters a circuit continuously or even intermittently
(e.g. in under-floor heating systems whose pipes are not pro-
tected by impermeable synthetic sheaths, in circuits with open
expansion vessels, or in circuits that require frequent top-ups)
always separate the boiler’s water circuit from the central heat-
ing circuit.
To sum up, in order to eliminate contact between air and water (and to
prevent the latter from becoming oxidized), it is necessary:
- that the expansion system be a closed vessel, correctly sized
and with the correct pre-loading pressure (to be regularly
checked);