Access To The Main Components - Carrier 020-093 Installation, Operation And Maintenance Instructions

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

Caution: Before performing any work on the machine
ensure it is de-energised. Verify that the main power
to the unit is cut off .
It is mandatory to use all required PPE for work at
height. Pay special attention to units with lower
supply and/or return.
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.
Compressor
In the case of compressor replacement:
■ Disconnect the unit from power supply.
■ Completely drain the refrigerant charge using a specific
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.
N.b.: For some maintenance tasks, it may be convenient to access
the outdoor unit by lifting the cover with the fan(s). Consult the lift
procedure in the chapter "Fans and air ducts".
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:
R-410A
Main circuits:
50FF 020 028
Volume (l) C1: 2,5 C1: 2,5
50FF 052 058
Volume (l) C1: 3,6 C1: 5,0 C1: 5,0 C1: 5,0 C1: 6,5 C1: 6,8 C1: 6,8
50FC 020 028
Volume (l) C1: 2,5 C1: 2,5 C1: 3,3 C1: 3,5 C1: 3,5 C1: 3,5
50FC 058 062
C1: 2,5 C1: 2,5
Volume (l)
C2: 2,5 C2: 3,3
Cooling recovery circuit (optional):
50FF/FC 020 028
Volume (l) CR: 0,7 CR: 0,7 CR: 1,2 CR: 1,2 CR: 1,2 CR: 1,2 CR: 1,7
50FF/FC 058 062
Volume (l) CR: 1,7 CR: 1,7 CR: 1,8 CR: 1,8 CR: 1,8 CR: 1,8 CR: 1,8
037 040 045
C1: 3,3 C1: 3,5 C1: 3,5
062 070 074 086
037 040 045 047
070 074 086 093
C1: 3,3 C1: 3,3 C1: 3,5 C1: 3,5
C2: 3,3 C2: 3,5 C2: 3,5 C2: 3,5
037 040 045 047
070 074 086 093
047
C1: 3,5
093
052
C1: 2,5
C2: 2,5
099
C1: 5,0
C2: 5,0
052
099
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