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General information
EN
1.2.2 Vibration
Ensure regularly that the vibration levels remain accept-
able and close to those at the initial unit start-up.
No part of the unit must be used as a walkway, rack or
support. Periodically check and repair or if necessary re-
place any component or piping that show signs of dam-
age. Do not step on refrigeration lines.
The lines can break under the weight and release refriger-
ant, causing personal injury. Do not climb on a machine.
Use a platform, or staging to work at higher levels.
Do not introduce any significant static or dynamic pres-
sure into the heat exchange circuit with regard to the de-
sign operating pressures).
During any handling, maintenance and service operations
the engineers working on the unit must be equipped with
safety gloves, glasses, shoes and protective clothing. Pay
attention to burns when brazing.
If an oil draining or recovery operation becomes necessary,
the fluid transfer must be made using mobile containers.
The products that may be added for thermal insulation of
the containers during the water piping connection proce-
dure must be chemically neutral in relation to the materi-
als and coatings to which they are applied. This is also the
case for the products originally supplied by Carrier SCS.
Change the refrigerant after an equipment failure, follow-
ing a provided procedure or carry out a refrigerant analysis
in a specialist laboratory.
1.2.3 Water connections
Make sure there are not water leaks from the system.
Should the unit be shutdown for a long periods:
- open the drain valve installed on the hydronic mod-
ule and partially drain the pump and the water pipes
as well as the drain valve on the plate-type exchanger,
which must be installed on the hydraulic circuit.
- to completely drain the pump, remove the cap on it.
This operations is essential if temperatures are expect-
ed to drop below freezing.
If the unit is not drained, the main switch should remain
connected so that the defrost thermostat can operate.
Carefully clean the system water filter.
1.2.4 Recommendations
Riello recommendations on heat exchange fluids:
• No NH4+ ammonium ions in the water, they are very detri-
mental for 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 exchanger used for these units have brazed cop-
per joints).
• Cl-Chloride ions are detrimental for copper with a risk of
perforations by corrosion by puncture. If possible keep be-
low 10 mg/l.
• SO42 sulphate ions can cause perforating corrosion, if their
content is above 30 mg/l.
• No fluoride ions (<1,0 mg/l)
• No Fe2+ and Fe3+ ions with non negligible levels of dis-
solved oxygen must be present. Dissolved iron <5 mg/l with
dissolved oxygen <5 mg/l.
• Dissolved silicon: silicon is an acid element of water and
can also lead to corrosion risks. Content z1mg/l. wather
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 a detrimental to deoxy-
genate 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 600 µS/cm
• pH: ideal case pH neutral at 20-25°C – 7<pH<8
CAUTION:
If the water circuit must be emptied for longer than one
month, the complete circuit must be placed under nitro-
gen charge to avoid any risk of corrosion by differential
aeration.
CAUTION:
Periodically inspect all valves, fittings and pipes of the re-
frigerant and hydronic circuits to ensure that they do not
show any corrosion or any signs of leaks ; also on compo-
nents coating.
CAUTION:
Never use the compressor as a vacuum pump.
CAUTION:
When adjusting the refrigerant charge, always ensure
that water is circulating in the heat exchanger to prevent
any possibility of freezing up. Damage caused by freezing
is not covered by the product warranty.
1.2.5 Liquid refrigerant charge
Checking the charge
CAUTION:
Accidental exhaust of refrigerant, whether due to a small
leak or to a large discharge from a piping rupture, can
cause frostbites and burns to exposed person. Never ne-
glect such injures. The installers, owners and especially
the repairers for small outdoor units, must:
- set a procedure to consult medical experts prior to treat
such injuries,
- provide first aid equipment, especially for rapid treatment
of eyes injuries.
We recommend them to apply the EN378-3 Annex 3.
When adjusting the refrigerant charge, always ensure that
water is circulating in the heat exchanger to prevent any
possibility of freezing up. Damage caused by freezing is
not covered by the product warranty.
