9. When intervening inside the refrigerating circuit to carry out repairs or for any other
reason, the conventional procedures must be followed:
• remove the refrigerant;
• bleed the circuit with an inert gas;
• evacuate;
• bleed again with an inert gas;
• open the circuit by cutting or by means of brazing.
9a. Oxygen-Free Nitrogen (OFN) MUST be purged through the system both before and
during the brazing process.
9b. When the final OFN charge is used, the system must be discharged up to atmospheric
pressure to allow the execution of the work. This operation is absolutely essential if it
is desired to carry out brazing operations on the pipes.
10. The load of refrigerant must be stored in the specific custody cylinders. The system
must "cleaned" with OFN to make the unit safe. It may be necessary to repeat this
process several times. DO NOT use compressed air or oxygen for this operation.
10a. Make sure that contamination between different refrigerants does NOT occur when a
reloading equipment is used. The flexible pipes or ducts MUST be as short as possible
to reduce the quantity of refrigerant inside them to a minimum.
11. The cylinders must be kept in vertical position.
Only use cylinders suitable for collection of refrigerants. The cylinders must be complete
of a pressure-relief valve and switch off valves in good conditions.
A set of calibrated weighing scales must also be available.
12. The pipes must be equipped with couplings for disconnection and must NOT present
leaks. Before using the collection machine, check that it underwent correct maintenance
and that the possible associated electric components are sealed, to prevent switching
on in case of leak of refrigerant.
13. Make sure the refrigerating system is earthed before proceeding with reloading of the
system with refrigerant.
Label the system when reloading is complete.
Pay particular attention not to overload the refrigerating system.
14. Before proceeding with reloading, the system must undergo the pressure test with OFN
and the tightness test at the end of reloading, but before commissioning.
It is necessary to carry out an additional tightness test before leaving the site.
14a. Remove the refrigerant safely. Move the refrigerant in the cylinders suitable for recovery.
Make sure there is a correct number of cylinders to contain the charge entirely. All
cylinders are labelled for this type of refrigerant (special cylinders for refrigerant
recovery). The cylinders must be complete of a pressure relief valve and of and of the
corresponding closure valve in good conditions. Empty cylinders are evacuated and, if
possible, cooled down before recovery.
14b.Equipment for recovery must be within the range of the technician, in good conditions,
with a series of instructions and must be suitable for recovery of all the refrigerants
(even flammable ones). A series of calibrates scales must be available and in good
conditions. Check that the pipes are in good conditions and complete of disconnection
joints without losses.
14c. Before using the machine for recovery, check that it is in good operating conditions,
that it has been adequately maintained and that all the associated electric components
are sealed to prevent switching-in in case of release of refrigerant. In case of doubt,
please contact the manufacturer.
15. Collected refrigerant must be returned to the fluid supplier in the appropriate collection
cylinder, compiling the corresponding Handover Note of Scraps.
DO NOT mix the refrigerants in the collection units and, in particular, in the cylinders.
16. Make sure that contamination between different refrigerants does not occur when a
reloading equipment is used. The flexible pipes or ducts must be as short as possible
to reduce the quantity of refrigerant inside them to a minimum.
17. Do not drill nor burn the unit.
18. The replaced electric components MUST be suitable and correspond to the appliance
specifications. Every maintenance operation MUST be carried out as described in this
manual. Contact the manufacturer in case of doubt.
EN - 5
ARYAL S2 E DUAL / TRIAL