Electrolux EXP09HSECI User Manual page 20

20 www.electrolux.com
servicing, then a permanently operating
form of leak detection shall be located
at the most critical point to warn of a
potentially hazardous situation�
2. Particular attention shall be paid to the
following to ensure that by working on
electrical components, the casing is not
altered in such a way that the level of
protection is affected� This shall include
damage to cables, excessive number
of connections, terminals not made to
original specification, damage to seals,
incorrect fitting of glands, etc� Ensure
that apparatus is mounted securely�
Ensure that seals or sealing materials
have not degraded such that they no
longer serve the purpose of preventing
the ingress of flammable atmospheres�
Replacement parts shall be in
accordance with the manufacturer's
specifications�
NOTE: The use of silicon sealant may
inhibit the effectiveness of some types of
leak detection equipment� Intrinsically safe
components do not have to be isolated
prior to working on them�
Repair to intrinsically safe
components
Do not apply any permanent inductive or
capacitance loads to the circuit without
ensuring that this will not exceed the
permissible voltage and current permitted
for the equipment in use�
Intrinsically safe components are the only
types that can be worked on while live in
the presence of a flammable atmosphere�
The test apparatus shall be at the correct
rating� Replace components only with
parts specified by the manufacturer� Other
parts may result in the ignition of refrigerant
in the atmosphere from a leak�
Cabling
Check that cabling will not be subject
to wear, corrosion, excessive pressure,
vibration, sharp edges or any other
adverse environmental effects� The check
shall also take into account the effects of
aging or continual vibration from sources
such as compressors or fans�
Detection of flammable refrigerants
Under no circumstances shall potential
sources of ignition be used in the
searching for or detection of refrigerant
leaks� A halide torch (or any other detector
using a naked flame) shall not be used�
Leak detection methods
The following leak detection methods are
deemed acceptable for systems containing
flammable refrigerants�
Electronic leak detectors shall be used
to detect flammable refrigerants, but the
sensitivity may not be adequate, or may
need re-calibration� (Detection equipment
shall be calibrated in a refrigerant-free
area�) Ensure that the detector is not a
potential source of ignition and is suitable
for the refrigerant used� Leak detection
equipment shall be set at a percentage
of the LFL of the refrigerant and shall be
calibrated to the refrigerant employed and
the appropriate percentage of gas (25 %
maximum) is confirmed�
Leak detection 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�
If 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�
Removal and evacuation
When 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:
• Remove refrigerant;
• Purge the circuit with inert gas;
• Evacuate;