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30RB/30RQ - 30RBY
Carrier recommendations on heat exchange fluids:
• No NH
ammonium ions in the water, they are very detrimental for
4+
copper. This is one of the most important factors for the operating life of
copper piping. A content of several tenths of mg/l will badly corrode the
copper over time (the plate heat exchangers used for these units have
brazed copper joints).
• Cl- Chloride ions are detrimental for copper with a risk of perforations
by corrosion by puncture. If possible keep below 10 mg/l.
• SO42- sulfate ions can cause perforating corrosion, if their content is
above 30 mg/l.
• No fluoride ions (<0.1 mg/l).
• No Fe
and Fe
ions with non negligible levels of dissolved oxygen must
2+
3+
be present. Dissolved iron < 5 mg/l with dissolved oxygen < 5 mg/l.
• Dissolved silica: silica is an acid element of water and can also lead to
corrosion risks. Content < 1mg/l. Water hardness: > 0.5 mmol/l. Values
between 1 and 2.5 can be recommended. This will facilitate scale deposit
that can limit corrosion of copper. Values that are too high can cause
piping blockage over time. A total alkalimetric titre (TAC) below 100 is
desirable.
• Dissolved oxygen: Any sudden change in water oxygenation conditions
must be avoided. It is as detrimental to deoxygenate the water by
mixing it with inert gas as it is to over-oxygenate it by mixing it with
pure oxygen. The disturbance of the oxygenation conditions encourages
destabilisation of copper hydroxides and enlargement of particles.
• Electric conductivity 600µS/cm
• pH: Ideal case pH neutral at 20-25°C - 7 < pH < 8
Do not introduce any significant static or dynamic pressure into the heat
exchange circuit (with regard to the design operating pressures).
13
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