Nibe S2125 Sicherheitsinformationen Seite 25

leak, if this part of the system can be dis-
connected safely with shut-off valves. The
system must be emptied in accordance
with the section "Removal and draining".
REMOVAL AND DRAINING
When a cooling circuit is opened for repairs
– or for another reason– work must be car-
ried out in a conventional manner. Due to
the risk of fire it is important that best
practice is applied. Follow the procedure
below.
Remove the refrigerant
1.
Flush the circuit with inert gas.
2.
Drain the circuit.
3.
Flush through with inert gas.
4.
Open the circuit by cutting or brazing.
5.
Collect the refrigerant in the intended cyl-
inders. Clean the system with oxygen-free
nitrogen to make the unit safe. This process
may need to be repeated several times.
Compressed air and oxygen must not be
used.
Clean the system by breaking the vacuum
with oxygen-free nitrogen, and filling the
system to working pressure, relieving the
pressure to atmospheric pressure and fi-
nally pumping to vacuum. Repeat the pro-
cess until no refrigerant remains in the
system. After the final filling with oxygen-
free nitrogen, relieve the pressure in the
system to atmospheric pressure, so that
work can be carried out. This type of flush-
ing must always be carried out if hot work
is to be performed on the pipe system.
Ensure that the vacuum pump's outlet is
not near to any potential ignition sources
and that there is satisfactory ventilation by
the outlet.
FILLING
In addition to the conventional filling pro-
cedures, the following actions must be
taken.
S2125 | GB
Ensure that different refrigerants are not
•
mixed when filling equipment is used.
Hoses and lines must be as short as pos-
sible to minimise the enclosed refrigerant
volume.
Containers must be stored in a suitable
•
position in accordance with the instruc-
tions.
Ensure that the cooling system is groun-
•
ded before the system is filled with refri-
gerant.
Mark the system once filling is complete
•
(if not already marked). If the amount dif-
fers from the pre-installed amount, the
marking must include the pre-installed
amount, the added extra amount and the
total amount.
Take extra care not to overfill the cooling
•
system.
Before refilling the system, pressure test it
with oxygen-free nitrogen. Leak test the
system after filling but before using the
system. Perform an additional leak test be-
fore leaving the installation.
DECOMMISSIONING
Before the device is taken out of operation,
the technician must without exception be
very familiar with the equipment and all its
component parts. Good practice prescribes
that all refrigerant is collected safely. Be-
fore the collected refrigerant can be reused,
oil and refrigerant samples must be taken,
if analysis is required. There must be a
power supply when this task is started.
Familiarise yourself with the equipment
1.
and its use.
Isolate the system electrically.
2.
Before starting the procedure, ensure
3.
that:
necessary equipment for mechanical
•
handling of the refrigerant container
is available
all necessary personal safety equip-
•
ment is available and used correctly
the collection process is continuously
•
supervised by an authorised person
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