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Contact the technical office to request information on the performance of the pre-heating coil when it is filled with a type of glycol other than
ethylene.
Check that the glycol used is compatible with the materials that make up the hydraulic circuit and the heat exchange coils.
Check that the water contained in the hydraulic circuit respects the following characteristics for the whole lifetime of the system:
1
2
Presence of calcium (Ca) and magnesium (Mg)
3
4
5
6
7
8
9
10
11
where:
1/1.78 °D=1 °Fr with 1°Fr= 10 gr CaCO
ppm = parts per million;
Explanatory notes
Ref. 1:
a greater concentration of hydrogen ions (pH) than 9 implies a high risk of deposits, whereas a lower pH than 7 implies
a high risk of corrosion;
Ref.2:
The hardness measures the amount of Ca and Mg carbonate dissolved in the water with a temperature lower than
100 °C (temporary hardness).
A high hardness implies a high risk of deposits;
Ref. 3:
the concentration of chloride ions with higher values than those indicated causes corrosion;
Ref.4 - 5 - 8: the presence of iron and manganese ions and oxygen leads to corrosion;
Ref. 6 - 7:
carbon dioxide and hydrogen sulphide are impurities that promote corrosion;
Ref. 9:
Usually in water from the waterworks it is a value of between 0.2 and 0.3 ppm. High values cause corrosion;
Ref.10:
the presence of ammonia reinforces the oxidising power of oxygen;
Ref. 11:
Below the value shown in the table, there is a risk of corrosion due to the trigger of galvanic currents between copper
and other less noble metals.
In the case of service fluids other than water (e.g. ethylene or propylene glycol), it is advisable to always use fluids containing special
inhibitors that offer thermal stability within the operating temperature ranges and protection against corrosion phenomena.
It is absolutely essential that, in the presence of dirty and/or aggressive water, an intermediate heat exchanger is placed upstream
of the refrigeration system heat exchangers.
The presence of air in the hydraulic circuit reduces the performance and can cause serious malfunctions and defects to the pumping
system in particular. All the air must be released out of the air bleed valves of the unit and system and not allowed to enter again
when setting up the hydraulic connection of the unit.
If the unit is to be put in storage for a long time, it is advisable to dry the heat exchangers and pressurise them with nitrogen to
prevent humidity from lingering in the hydraulic circuit.
Description
Concentration of hydrogen ions
Chloride ions
Iron ions
Manganese ions
Carbon dioxide
Hydrogen sulphide
Oxygen
Chlorine
Ammonia
ratio between carbonates and sulphates
ppb = parts per billion
Symbol
pH
Hardness
-
Cl
3+
Fe
2+
Mn
CO
2
H
S
2
O
2
Cl
2
NH
3
HCO
/ SO
3-
3
/ m
3
IUM_WIZARDX_03_22_EN
Value
7.5 9
4 8.5 °D
< 150 ppm
< 0.5 ppm
< 0.05 ppm
< 10 ppm
< 50 ppb
< 0.1 ppm
< 0.5 ppm
< 0.5 ppm
2-
> 1
4
Tab.4
47
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