Step 6: Establishment Of Atex Zones; Step 7: Labeling The Unit; Step 8: Commissioning - Carrier 50FC Serie Instrucciones De Retrofit

3 - RETROFIT FOR THE REPLACEMENT OF R-410A BY R-454B
The new charge value is indicated in the following table:
Main circuits:
50FC 100 110
C1: 15.5 C1: 15.5
Charge (kg)
C2: 15.5 C2: 15.5
Environ.
C1: 7.2 C1: 7.2
impact
C2: 7.2 C2: 7.2
(t CO2e)
50FC 170 180
C1: 17.5 C1: 24.5
Charge (kg)
C2: 17.5 C2: 24.5
Environ.
C1: 8.2 C1: 11.4
impact
C2: 8.2 C2: 11.4
(t CO2e)
Cooling recovery circuit (optional):
50FC 100 110
Charge (kg) C3: 4.8 C3: 4.8
Environ.
impact C3: 2.2 C3: 2.2
(t CO2e)
50FC 170 180
Charge (kg)
C3: 5.8 C3: 6.8
Environ.
impact
C3: 2.7 C3: 3.2
(t CO2e)
● This change must be recorded in the unit's logbook. It
should contain the quantity the quantity and type of recycled
fl uid (R-410A), the quantity and type of fl uid present within
the installation (R-454B), the date and output of the leak test,
and the identity and designation of the retrofi t operator.

Step 6: Establishment of ATEX zones

● ATEX zones of 0.6 meters should be established around the
unit, due to the nature of this refrigerant (A2L fl uid), as shown
in the following diagram.
ATEX zone 2 is involved.
10
120 130 145 160
C1: 15.5 C1: 17.0 C1: 17.0 C1: 17.3
C2: 15.5 C2: 17.0 C2: 17.0 C2: 17.3
C1: 7.2 C1: 7.9 C1: 7.9 C1: 8.0
C2: 7.2 C2: 7.9 C2: 7.9 C2: 8.0
200 220 250 280
C1: 25.5 C1: 25.5 C1: 30.5 C1: 31.0
C2: 25.5 C2: 25.5 C2: 30.5 C2: 31.0
C1: 11.9 C1: 11.9 C1: 14.2 C1: 14.4
C2: 11.9 C2: 11.9 C2: 14.2 C2: 14.4
120 130 145 160
C3: 4.8 C3: 5.8 C3: 5.8 C3: 5.8
C3: 2.2 C3: 2.7 C3: 2.7 C3: 2.7
200 220 250 280
C3: 6.8 C3: 6.8 C3: 10.7 C3: 10.7
C3: 3.2 C3: 3.2 C3: 5.0 C3: 5.0
0,6m
0,6m
0,6m
The ATEX zones, as defi ned, must only be entered by suitably
trained personnel equipped with the appropriate detection
material and tools for working in an ATEX zone.
These units are designed to be installed outdoors, in a free
fi eld-type, well ventilated area.
As the refrigerant used is heavier than air, it is essential
that installations joined to the unit prevent the retention of
refrigerant at the lowest point in the event of a leak.
In the ATEX zones, the presence of ignition sources (electrical,
thermal, etc.) is prohibited, even temporarily. They also cannot
be installed in or near the duct network of the unit.
In these zones, the installation of fresh air vents or extractors
of the building is also prohibited.

Step 7: Labeling the unit

● Remove the sticker corresponding to the R-410A refrigerant
located inside the electrical cabinet.
● Place the fl ammable gas sticker next to the name plate.
● Modify the following data on the name plate:
- Name of refrigerant.
- Maximum operating pressures of the high side (40.5 bar)
and the low side (24.0 bar).
- Amount of refrigerant.
Important: It is the responsibility of the customer to make
all these changes.

Step 8: Commissioning

● When all the above steps have been completed, the unit will
be put into operation. This should be done by following all
recommendations given in chapter 13 "Commissioning" of
the instruction manual.
After commissioning, the correct operation of the unit must be
checked by reviewing the safety elements, especially the high
and low pressure securities, because they ensure operation
within the permissible limits.
Important: A high pressure failure must be caused in each
of the circuits to verify the operation of the high pressure
switches. Set value: 40.5 bar.
Note: The safety valve installed in the unit does not need any
adaptation due to the change of refrigerant, as both have
similar working pressures. Set value: 45 bar.
To make sure that the unit is fi lled with the correct charge of
refrigerant, check the values of overheating and subcooling,
circuit by circuit, with the system running at full capacity..
To adjust the refrigerant charge, each circuit has a schrader-
type valve in the liquid line.
Observe if alarms occur in electronic control (see the historical
alarms record).
The recording of the main parameters whilst the unit is running
allows controlling the installation performance and it is the best
possible way to avoid breakdowns since the analysis of these
data makes early detection of anomalies possible.