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remove the refrigerant;
purge the circuit with an inert gas (optional for A2L);
drain (optional for A2L);
purge with an inert gas (optional for A2L);
open the circuit by cutting or soldering.
The refrigerant charge must be recovered in suitable recovery cylinders. For appliances containing
flammable refrigerants other than A2L refrigerants, the system must be bled with nitrogen devoid of oxygen
to make the appliance suitable for receiving flammable refrigerants. You may need to repeat this process
several times. Compressed air or oxygen must not be used to purge cooling systems.
Loading procedures
Check that the vacuum pump outlet is not located in the vicinity of any potential ignition source and that
ventilation is provided.
In addition to conventional charging procedures, the following requirements apply.
Check that there is no possibility of cross-contamination between the different refrigerants when using
charging equipment. Hoses or lines must be as short as possible to reduce the quantity of refrigerant
contained therein.
Cylinders must be kept in an appropriate position, in accordance with the instructions.
Check that the cooling system is grounded before charging the system with refrigerant.
Label the system once charging is complete (if this is not already the case).
Pay close attention to not overfilling the cooling system.
Before recharging the system, carry out a pressure test using a suitable purge gas. The system must be
examined to make sure there are no leaks after the charging operation and before commissioning. A follow-
up leak test must be carried out before leaving the site.
Dismantling
Before dismantling, the technician must familiarise himself/herself with the equipment and its specifications.
We highly recommend carefully recovering all refrigerants. Before this, oil and refrigerant samples must be
taken if analyses are to be carried out before any other use of the recovered refrigerant. Check for the
presence of a power supply before starting work.
1.
Familiarise yourself with the equipment and how it operates.
2.
Electrically isolate the system.
3.
Before starting work, check the following points:
mechanical handling equipment is available if needed to handle the refrigerant cylinders;
all personal protective equipment is available and used correctly;
the recovery process is followed at all times by a cognizant person;
the recovery cylinders and equipment comply with the relevant standards.
4.
Drain the cooling system where possible.
5.
If a vacuum cannot be created, install a manifold in order to be able to remove the refrigerant from
various locations within the system.
6.
Make sure that the cylinder is located on the scales before starting recovery operations.
7.
Start the recovery unit and operate as per its instructions.
8.
Do not overfill the cylinders (no more than 80% of the volume must be filled with liquid).
9.
Do not exceed the maximum working pressure of the cylinder, even temporarily.
10. When the cylinders have been filled correctly and the process is complete, check that the cylinders and
the equipment are quickly removed from the site and that the alternative shut-off valves on the
equipment are closed.
11. The recovered refrigerant must not be charged in another cooling system, unless it has been cleaned
and inspected.
TROUBLESHOOTING
All brazing must be carried out by qualified brazers.
Replacement pipes must always be made of copper in compliance with standard NF EN 12735-1.
Leak detection; pressure test:
never use oxygen or dry air, risk of fire or explosion,
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