Ohyama woozoo IPE-1221G, Руководство пользователя, Страница: 22 / 120

18
EN
Specialist’s anual
since flammability is a consideration. The following
procedure shall be adhered to:
● remove refrigerant;
● purge the circuit with inert gas;
● evacuate;
● purge again with inert gas;
● open the circuit by cutting or brazing.
The refrigerant charge shall be recovered into the
correct recovery cylinders. For appliances containing
flammable refrigerants, the system shall be “flushed"
with OFN to render the unit safe. This process may
need to be repeated several times. Compressed air
or oxygen shall not be used for purging refrigerant
systems.
For appliances containing flammable refrigerants,
flushing shall be achieved by breaking the vacuum in
the system with OFN and continuing to fill until the
working pressure is achieved, then venting to
atmosphere, and finally pulling down to a vacuum.
This process shall be repeated until no refrigerant is
within the system. When the final OFN charge is
used , the system shall be vented down to
atmospheric pressure to enable work to take place.
This operation is absolutely vital if brazing operations
on the pipe-work are to take place.
Ensure that the outlet for the vacuum pump is not
close to any ignition sources and that ventilation is
available.
Charging procedures
ln addition to conventional charging procedures, the
following requirements shall be followed.
- Ensure that contamination of different refrigerants
does not occur when using charging equipment.
Hoses or lines shall be as short as possible to
minimise the amount of refrigerant contained in
them.
- Cylinders shall be kept upright.
- Ensure that the refrigeration system is earthed prior
to charging the system with refrigerant.
- Label the system when charging is complete (if not
already).
- Extreme care shall be taken not to overfill the
refrigeration system.
Prior to recharging the system, it shall be
pressure-tested with the appropriate purging gas.
The system shall be leak-tested on completion of
charging but prior to commissioning. A follow up
leak test shall be carried out prior to leaving the site.
Decommissioning
Before carrying out this procedure, it is essential that
the technician is completely familiar with the
equipment and all its detail. It is recommended good
practice that all refrigerants are recovered safely. Prior
to the task being carried out, an oil and refrigerant
sample shall be taken in case analysis is required prior
to reuse of reclaimed refrigerant. It is essential that
electrical power is available before the task is
commenced.
a) Become familiar with the equipment and its
operation.
b) lsolate system electrically.
c) Before attempting the procedure, ensure that:
● mechanical handling equipment is available, if
required, for handling refrigerant cylinders;
● all personal protective equipment is available and
being used correctly;
● the recovery process is supervised at all times by a
competent person;
● recovery equipment and cylinders conform to the
appropriate standards.
d) Pump down refrigerant system, if possible.
e) If a vacuum is not possible, make a manifold so that
refrigerant can be removed from various parts of the
system.
f) Make sure that cylinder is situated on the scales
before recovery takes place.
g) Start the recovery machine and operate in
accordance with manufacturer's instructions.
h) Do not overfill cylinders. (No more than 80 %
volume liquid charge).
i ) Do not exceed the maximum working pressure of
the cylinder, even temporarily.
j) When the cylinders have been filled correctly and
the process completed, make sure that the cylinders
and the equipment are removed from site promptly
and all isolation valves on the equipment are closed
off.
k) Recovered refrigerant shall not be charged into
another refrigeration system unless it has been
cleaned and checked.
Labelling
Equipment shall be labelled stating that it has been
decommissioned and emptied of refrigerant. The label
shall be dated and signed. For appliances containing
flammable refrigerants, ensure that there are labels on
the equipment stating the equipment contains
flammable refrigerant.
Recovery
When removing refrigerant from a system, either for
servicing or decommissioning, it is recommended
good practice that all refrigerants are removed safely.
Specialist’s anual
When transferring refrigerant into cylinders, ensure
that only appropriate refrigerant recovery cylinders
are employed. Ensure that the correct number of
cylinders for holding the total system charge are
available. All cylinders to be used are designated for
the recovered refrigerant and labelled for that
refrigerant (i.e. special cylinders for the recovery of
refrigerant). Cylinders shall be complete with
pressure-relief valve and associated shut-off valves
in good working order. Empty recovery cylinders are
evacuated and, if possible, cooled before recovery
occurs.
The recovery equipment shall be in good working
order with a set of instructions concerning the
equipment that is at hand and shall be suitable for
the recovery of all appropriate refrigerants including,
when applicable, flammable refrigerants. ln addition,
a set of calibrated weighing scales shall be available
and in good working order. Hoses shall be complete
with leak-free disconnect couplings and in good
condition. Before using the re-covery machine, check
that it is in satisfactory working order, has been
properly maintained and that any associated
electrical components are sealed to prevent ignition
in the event of a refrigerant release. Consult
manufacturer if in doubt.
The recovered refrigerant shall be returned to the
refrigerant supplier in the correct recovery cylinder,
and the relevant waste transfer note arranged. Do
not mix refrigerants in recovery units and especially
not in cylinders.
lf compressors or compressor oils are to be
removed, ensure that they have been evacuated to
an acceptable level to make certain that flammable
refrigerant does not remain within the lubricant. The
evacuation process shall be carried out prior to
returning the compressor to the suppliers. Only
electric heating to the compressor body shall be
employed to accelerate this process. When oil is
drained from a system, it shall be carried out safely.