Danfoss iC7 Series Operating Manual page 27

iC7 Series Cooling Modules
Operating Guide
DAMAGE TO SYSTEM FROM THE USE OF HYDROCARBONS
Hydrocarbons damage the rubber seals of the cooling system.
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Do not use hydrocarbons (for example mineral oil) as coolant. Do not mix hydrocarbons to coolant.
Table 6: Requirements for the Purified Water
Property
pH
Chlorides
Sulphate ions
Maximum particle size
Total dissolved solids
Total hardness (CaCO )
3
Hydrogen carbonate
Electrical conductivity
6.8 Coolant Quality in the External Circuit
The coolant quality in the external circuit does not need to be as good as in the drive circuit. However, a good-quality coolant
makes the cleaning interval of the heat exchanger (HX11) longer. Do not use seawater as coolant. Freshwater from lakes or rivers
can be used.
The coolant must not contain particles that are larger than 1.5 mm (0.06 in). If there are larger particles in the coolant circulation, the
3-way valve or the heat exchanger can become clogged. To filter out large particles, install a filter (MF21) at the external circuit inlet.
The mesh size of the filter must be < 1.5 mm (0.06 in).
The coolant must not include any chemicals, for example, high amounts of chloride, chlorine, or oil. The amount of free chlorine
must be < 5 mg/l (< 0.0007 oz/gal). Oil damages the EPDM rubber seals of the cooling module.
A natural source of water can include organic sediment. The organic sediment attaches to the plates inside the heat exchanger. The
organic sediment also increases the pressure loss over the heat exchanger and therefore the flow decreases. These factors make the
liquid-to-liquid heat transfer between the drive and the external circuit less efficient.
Because of possible organic sediment, install flow measuring or pressure difference measuring equipment. This equipment gener-
ates an alarm if the flow is below the requirements. It is also recommended to set leakage sensors in the external circuit.
See 10.2 Cleaning the Heat Exchanger
CLOGGING OF THE HEAT EXCHANGER
If the coolant quality in the external circuit is not sufficient, the heat exchanger can become clogged. A clogged heat exchanger
decreases the flow in the cooling module and makes the cooling module less efficient.
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Use a coolant that meets the requirements.
6.9 Purified Water as Coolant
Purified water can be used as coolant if there is no risk of freezing. Freezing water permanently damages the cooling system. Puri-
fied water is demineralized, deionized, or distilled water.
Always use an inhibitor Cortec VpCI-649 with 1.0% of volume with purified water.
Danfoss A/S © 2022.02
N O T I C E
Required value
6...8
≤ 25 ppm
≤ 25 ppm
≤ 50 µm
≤ 200 ppm
3...4.6 dH° (53...80 ppm)
≤ 50 ppm
≤ 500 µS/cm
for the cleaning instructions of the heat exchanger.
C A U T I O N
Cooling Installation
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