CLIVET ELFOFresh EVO CPAN-YIN, Manual For Installation, Use And Maintenance

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9 - MAINTENANCE
Under no circumstance is it possible to use
potential ignition sources to search or detect
refrigerant leaks.
Do not use halide lights (or any other open flame
detectors).
Leak detection methods
The following leak detection methods are
considered acceptable for systems containing
flammable refrigerants. Electric leak detectors must
always be used to identify flammable refrigerants,
although they do not present a suitable sensitivity
level or require recalibration (detection equipment
must be calibrated in an area free from
refrigerants).
Check that the detector is not a possible source of
ignition and that it is suitable for the refrigerant.
Leak detection equipment must always be set to an
LFL percentage and calibrated depending on the
refrigerant used, so the correct gas percentage
(25% max) must be verified.
Leak detection fluids are suitable for most
refrigerants, although using detergents containing
chlorine should be avoided as this substance may
react with the refrigerant and corrode copper pipes.
If a leak is suspected, all open flames must be
removed or switched off.
If a leak is identified that requires brazing, all the
refrigerant must be recovered from the system or
isolated (using interception valves) in a section of
the system far away from the leak. Oxygen-Free-
Nitrogen (OFN) is then purged through the system
both before and during the brazing procedure.
Removal and evacuation
When intervening on the cooling circuit to perform
repair work or any other type of work, always
follow the normal procedure. However, considering
the risk of flammability, we recommend following
the best practices. Comply with the following
procedure:
•
remove the refrigerant;
•
purge the circuit with inert gas;
•
evacuate;
•
Purge again with inert gas;
•
Interrupt the circuit with interruption or brazing.
The refrigerant charge must be collected in suitable
recovery tanks. To make the unit safe, flushing with
Oxygen-free-Nitrogen must be performed. This
procedure may have to be repeated multiple times.
Do not use compressed air or oxygen for this
operation.
Flushing is obtained interrupting the system vacuum
with OFN and filling until the operating pressure is
obtained, then releasing into the atmosphere and
restoring the vacuum. This process must be
Repairing sealed components
•
During the reparation operations of sealed
•
components, disconnect all the equipment before
removing sealed casings etc. If, during
operations, it is absolutely necessary for the
equipment to remain connected, a leak detection
device must be placed in the most critical point
so as to report any potentially-dangerous
situation.
•
Pay particular attention to what follows to
guarantee that, while intervening on electrical
components, the housing is not altered in a way
so as to affect the level of protection. This
includes damage to cables, an excessive number
of connections, terminals not compliance with
the original specifications, damage to gaskets, an
unsuitable installation of gaskets, etc.
•
Make sure the device is installed safely.
•
Check that the seals or sealing materials are not
altered in such a way that they no longer the
impede the entry of flammable environments.
Spare parts must comply with manufacturer
specifications.
NOTE:

Using silicone sealants may inhibit
the effectiveness of a few types of
leak detection equipment. It is not
necessary to isolate intrinsically safe
components before performing
operations on them.
Reparation of intrinsically safe components
Do not apply permanent inductive or capacitive
loads to the circuit without making sure that they
do not exceed the admissible voltage and current
allowed for equipment in use.
Intrinsically safe components are the only
component type on which operations can be
performed in a flammable atmosphere. The testing
device must show a correct value. Replace
components only with the parts specified by the
manufacturer.
Following a leak, other parts could lead to the
combustion of the refrigerant in the atmosphere.
Wires
Make sure wires are not subjected to wear,
corrosion, excessive pressure or vibration, that there
are no sharp edges and that they do not produce
other negative effects on the environment. The
inspection must also keep into consideration the
effects of tine or the continuous vibration caused
e.g. by compressors or fans.
Detection of flammable refrigerants
SAFETY WARNINGS FOR OPERATIONS ON UNITS CONTAINING R32