Removal And Evacuation; Charging Procedures - Qlima D 720 Cube Gebrauchsanweisung

fluids are suitable for use with most refrigerants but the use of detergents
containing chlorine shall be avoided as the chlorine may react with the refrigerant
and corrode the copper pipe-work. If a leak is suspected, all naked flames shall be
removed/ extinguished.
I f a leakage of refrigerant is found which requires brazing, all of the refrigerant
shall be recovered from the system, or isolated (by means of shut off valves) in a
part of the system remote from the leak. Oxygen free nitrogen (OFN) shall then be
purged through the system both before and during the brazing process.

12. REMOVAL AND EVACUATION

W hen breaking into the refrigerant circuit to make repairs or for any other
purpose conventional procedures shall be used. However, it is important that best
practice is followed since flammability is a consideration. The following procedure
shall be adhered to:
R emove refrigerant; Purge the circuit with inert gas; Evacuate; Purge again with
inert gas; Open the circuit by cutting or brazing.
T he refrigerant charge shall be recovered into the correct recovery cylinders. 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 this
task. 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.
W hen 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 there is
ventilation available.

13. CHARGING PROCEDURES

I n 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.
E nsure that the refrigeration system is earthed prior to charging the system with
refrigerant.
Label the system when charging is complete (if not already).
E xtreme 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.
14. DECOMMISSIONING
B efore 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.
P rior 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) B efore 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) I f 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) S tart the recovery machine and operate in accordance with manufacturer's
instructions.
h) D o not overfill cylinders. (No more than 80 % volume liquid charge).
i) Do not exceed the maximum working pressure of thecylinder, even temporarily.
j) W hen the cylinders have been filled correctly and the process completed, make
sure that the cylinders and the equipment are removed from site promptly and
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