53
14 - MAINTENANCE
Level 3 maintenance
Maintenance at this level requires specifi c skills, qualifi cations,
tools and expertise. Only the manufacturer, his representative or
authorised agent are permitted to carry out this work.
This maintenance work relates to the following:
■ Replacement of major components (compressor, coil
exchanger, etc).
■ Operations on the refrigerant circuit (handling refrigerant).
■ Modifi cation of factory-set parameters (changes on the “50FC”
control);
■ Movement or disassembly of the refrigeration unit.
■ Any operation due to proven lack of maintenance.
■ Any operation covered by the warranty.
■ One or two leak detection operations per year performed by
qualifi ed personnel using a certifi ed leak detector.
■ To reduce waste, the refrigerant and the oil must be transferred.
■ In accordance with applicable regulations, using methods that
limit refrigerant leaks and pressure drops and with materials
that are suitable for the products.
■ Any leaks detected must be repaired immediately
■ The compressor oil that is recovered during maintenance
contains refrigerant and must be treated accordingly.
■ Pressurised refrigerant must not be vented to the open air.
■ If the refrigerating circuit must be opened, cap all openings for
a period of up to one day. If open for longer, blanket the circuit
with a dry, inert gas (e.g. nitrogen).
14.3 - Access to the main components
Important: Whenever maintenance work is carried out on a
unit with R-454B refrigerant, an A2L refrigerant detector must
be available, regardless of that installed inside the unit.
Caution: Before performing any work on the
machine ensure it is de-energised. Verify that the
main power to the unit is cut off .
Compressor
In the case of compressor replacement:
■ Disconnect the unit from power
supply.
■ Completely drain the refrigerant
charge using a specifi c recovery
machine for the type of refrigerant
included in the unit (R-410A or
R-454B).
Important: Always follow the
recommendations given in
section 2.2 “Safety standards for refrigerant”.
■ Disconnect electrically the compressor.
■ Carefully unsolder the suction and discharge piping.
■ The compressor is fi xed onto the platform with 4 screws.
■ Unscrew the fi xings.
■ Place the new compressor and check that it has a suffi cient
oil charge.
Warning: when tightening the compressor screws, please
consult the maximum torque that can be applied.
■ Solder the suction and discharge piping.
■ Connect the compressor in accordance with the wiring diagram.
■ Make vacuum and next, reload the gas into the unit according
to charge data provided in the table of section “Refrigerant”
and in the unit’s name plate.
Oil
Oils for refrigeration units do not pose any health risks if they are
used in compliance with the precautions for use:
■ Avoid unnecessary handling of components lubricated with oil.
Use protective creams.
■ Oils are fl ammable and must be stored and handled with care.
Disposable rags or cloths used in cleaning must be kept away
from open fl ames and disposed of in the appropriate manner.
■ Containers must be stored with their caps on. Avoid using oil
from an opened container stored under incorrect conditions.
■ Check the oil level and aspect. In case of a colour change,
check the oil quality using a contamination test.
■ In the case of the presence of acid, water or metallic particles,
replace the aff ected circuit oil, as well as the fi lter drier.
■ If all the oil must be emptied, replace it imperatively with new
oil of the same grade as the original oil which has been stored
in a hermetically sealed container until its time of use.
■ The oil type recommended for these units is:
Copeland 3MAF 32cST, Danfoss POE 160SZ, ICI Emkarate
RL 32CF, Mobil EAL Artic 22CC.
The following table indicates the required volume:
Main circuits:
Cooling recovery circuit (optional):
50FC 100 110 120 130 145 160
Volume (l) 4 x 3,0
2 x 3,0
+
2 x 3,3
4 x 3,3 4 x 3,3 4 x 3,3 4 x 3,3
50FC 170 180 200 220 250 280
Volume (l)
2 x 3,3
+
2 x 3,6
2 x 3,3
+
2 x 3,6
3 x 3,6
+
1 x 6,1
1 x 3,6
+
3 x 6,1
4 x 6,1 4 x 6,1
50FC 100 110 120 130 145 160
Volume (l) 3,0 3,0 3,0 3,3 3,3 3,3
50FC 170 180 200 220 250 280
Volume (l) 3,3 3,3 3,3 3,3 3,6 3,6
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