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2.2. Particular attention should be paid to the following points in order to ensure that the work
carried out on the electrical components does not modify the case in such a way as to impair the
level of protection.
This includes damaged cables, excessive number of connections, terminals not meeting original
specifications, damaged gaskets, improper mounting of cable glands, etc.
Make sure the device is mounted correctly. Make sure that the gaskets or sealing materials have
not degraded so that they no longer serve to prevent the infiltration of flammable atmospheres.
Replacement parts must conform to the manufacturer's specifications.
NOTE: The use of a silicone-based sealant may affect the effectiveness of some
types of leak detection equipment. Intrinsically safe components do not necessarily have to be
isolated before being worked on.
3. REPAIR OF INTRINSICALLY SAFE COMPONENTS
Do not apply any permanent inductive or capacitive load to the circuit without ensuring that it will
not exceed the allowable voltage and current for the equipment being used. Intrinsically safe
components are the only types that can be worked on when energized in a flammable
atmosphere. The test apparatus must be properly calibrated. Replace components only with parts
specified by the manufacturer.
Any other part may cause refrigerant to ignite in the atmosphere by leaking.
4. WIRING
Make sure that the wiring will not be subject to wear, corrosion, excessive pressure, vibration,
sharp edges or any other adverse effect on the environment. The verification should also take into
account the effects of aging or continual vibration from sources such as compressors or fans.
5. DETECTION OF FLAMMABLE REFRIGERANTS
Under no circumstances should potential ignition sources be used to search for or detect
refrigerant leaks. A halide torch (or any other detector using an open flame) should not be used.
6. LEAK DETECTION METHODS
The following leak detection methods are considered acceptable for systems containing
flammable refrigerants. Electronic leak detectors should be used to detect flammable refrigerants,
but the sensitivity may not be adequate or require recalibration (detection equipment should be
calibrated in an area without refrigerant). Make sure that the detector is not a potential source of
ignition and that it is suitable for the refrigerant used. Leak detection equipment should be set to a
percentage of the LLI of the refrigerant and should be calibrated with the refrigerant being used
and the correct gas percentage (25% maximum) is confirmed. Leak detection fluids can be used
with most refrigerants, however, the use of detergents containing chlorine should be avoided as
chlorine can react with the refrigerant and cause corrosion of copper pipes. If a leak is suspected,
all open flames should be removed / extinguished. If a refrigerant leak requiring brazing is
detected, all refrigerant should be recovered from the system or isolated (by means of shutoff
valves) in a part of the system remote from the leak. The oxygen free nitrogen (OFN) must then
be purged through the system before and during the brazing process. If a refrigerant leak
requiring brazing is detected, all refrigerant should be recovered from the system or isolated (by
means of shutoff valves) in a part of the system remote from the leak. The oxygen free nitrogen
(OFN) must then be purged through the system before and during the brazing process. If a
refrigerant leak requiring brazing is detected, all refrigerant should be recovered from the system
or isolated (by means of shutoff valves) in a part of the system remote from the leak. The oxygen
free nitrogen (OFN) must then be purged through the system before and during the brazing
process.
7. DRAINING AND EVACUATION
When entering the refrigerant circuit for repairs or for any other purpose, use conventional
procedures. However, it is important to follow best practices as flammability is a factor to consider.
The following procedure must be observed
: drain the refrigerant; purge the circuit with inert gas; clear out ; purge again with a
EN-11
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