5
User
’s Manual
What is hardness?
Hardness is the quantity of scaling
salts present in water, which are mainly
composed of low solubility salts of
calcium and magnesium. The main salts
causing hardness are listed below:
Calcium bicarbonate:
Ca(CO
3
H)
2
Calcium chloride:
CaCl
2
Calcium sulphate:
CaSO
4
Magnesium bicarbonate:
Mg(CO
3
H)
2
Magnesium chloride:
MgCl
2
Magnesium sulphate:
MgSO
4
These salts, due to their chemical
properties, have a tendency to
precipitate, producing scale on pipes and
obstructing them as they accumulate.
In the same way, hardness has a high
tendency to scale on the electrical
resistors from heaters and to precipitate
in heaters when temperature increases.
The combination of hard minerals and
soap produces a soap curdling, which
reduces the cleansing properties of
soap.
The precipitation of hard minerals builds
a layer on cooking utensils, connections
and plumbing fixtures. It may even alter
the taste of food.
Main problems:
• Precipitation
on pipes, fixtures and
appliances.
• Increase in energy consumption due to
generated isolation.
• Higher soap consumption.
• Reduction of the electrical appliances’
service life and increase of the
maintenance needed.
All these problems are greatly reduced
when using a water softening system.
For the most part of Europe, hardness is
indicated in French hydrometric degrees,
but there are also other measuring units,
according to each region.
The most common measurements to
follow.
UNITS
ppm
of CaCO
3
˚French
1 ppm of Calcium
2.5
0.25
1 ppm of Magnesium
4.13
0.413
1 ppm of CaCO
3
1
0.1
1º French (ºHF)
10
1
1º German (ºd)
17.8
1.78
1º English (ºe)
14.3
1.43
1 mmol/L
100
10
1 mval/L=meq/L
50
5
How does your system work?
Water softening is carried out by means
of an ion exchange process. The system
uses resin with the chemical capacity of
capturing Calcium (Ca) and Magnesium
(Mg) ions to remove them from water.
When Calcium and Magnesium ions
are captured by the resin, two Sodium
(Na) ions are released which, due to
its chemical properties, produce salts
with a higher solubility, thus avoiding all
hardness-related problems.
Therefore, when water gets softened,
its sodium level increases. Further
information on this procedure can be
found in ‘Section 2.8’.
Ion exchange resins:
These are synthetic compounds, usually
with a spherical shape, able to capture
certain chemical substances present
in water, which they then exchange
for other substances. Water softening
uses strong cation resins, which are
composed of styrene copolymers and
divinylbenzene with a sulphur base.
The exchange resin charge is inside the
column of the water softener and takes
up a significant part of the total volume.
During the process, water goes into the
Ergo valve through the inlet connection,
flows towards the bottom of the tank
through the distributing pipe and
goes upwards through the resin bed.
Treated water is collected by the upper
nozzle and supplied through the outlet
connection. At this point, the equipment
has a water meter which counts the
volume of treated water.
