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 shal 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 there is
ventilation available.
8. CHARGING PROCEDURES
In addition to conventional charging procedures,
the following requirements shall be followed.
– Ensure that contamination of different refriger-
ants 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 OFN. 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.
9. 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 re-use 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) Isolate 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.
10. LABELLING
Equipment shall be labelled stating that it has been
de-commissioned and emptied of refrigerant. The
label shall be dated and signed. Ensure that there
are labels on the equipment stating the equipment
contains flammable refrigerant.
11. RECOVERY
When removing refrigerant from a system, either for
servicing or decommissioning, it is recommended
good practice that all refrigerants are removed
safely.
When transferring refrigerant into cylinders, ensure
that only appropriate refrigeran recovery cylinders
are employed. Ensure that the correct number of
cylinders for holding the total system charge is
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
6
6
EN
Ref. 636134
DEHUMIDIFIER
DESHUMIFICADOR
