ENGLISH
WARNING
Prior to installation, ensure risk of ignition is minimised and avoid working in confined space.
Ensure adequate ventilation is available by opening windows or doors.
• When flared joints are reused indoors,the flare part shall be re-fabricated.
• Avoid installation of the air conditioner in a place where there is danger of exposure to continuously operating open flames
(for example an operating electric heaters).
• Any person who is involved with working on or breaking into a refrigerant circuit should hold a current valid certificate from an
industry-accredited assessment authority, which authorises their competence to handle refrigerants safely in accordance with an
industry recognised assessment specification.
•
Checking for presence of refrigerant
The area shall be checked with an appropriate refrigerant detector prior to and during work, to ensure the technician is aware of
potentially flammable atmospheres. Ensure that the leak detection equipment being used is suitable for use with flammable refrigerants,
i.e. nonsparking, adequately sealed or intrinsically safe.
•
Presence of fire extinguisher
If any hot work is to be conducted on the refrigeration equipment or any associated parts, appropriate fire extinguishing equipment shall
be available to hand. Have a dry powder or CO
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fire extinguisher adjacent to the charging area.
•
No ignition sources
All possible ignition sources, including cigarette smoking, should be kept sufficiently far away from the site of installation, repairing,
removing and disposal, during which flammable refrigerant can possibly be released to the surrounding space. “No Smoking” signs
shall be displayed.
•
The following checks shall be applied to installations:
– marking to the equipment continues to be visible and legible. Markings and signs that are illegible shall be corrected;
– refrigeration pipe or components are installed in a position where they are unlikely to be exposed to any substance which may
corrode refrigerant containing components, unless the components are constructed of materials which are inherently resistant to
being corroded or are suitably protected against being so corroded.
•
Initial safety checks shall include:
– that capacitors are discharged, this shall be done in a safe manner to avoid possibility of sparking
– there shall be no live electrical components and wiring are exposed while charging, recovering or purging the system;
•
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.
Replace components only with parts specified by the manufacturer.
•
Leak detection methods
Ensure that the detector is not a potential source of ignition (for example a halide torch) and is suitable for the refrigerant used. Leak
detection equipment shall be set at a percentage of the LFL of the refrigerant (for R32, LFL is 13%) 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 pipework. 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;
• purge again with inert gas;
• open the circuit by cutting or brazing.
The refrigerant charge shall be recovered into the correct recovery cylinders. The system shall be “flushed” with OFN to render the unit
safe. This process may need to be repeated several times.
Compressed air or oxygen shall not be used for this task. Flushing shall be achieved by breaking the vacuum in the system with OFN
and continuing to fill until the working pressure is achieved, then venting to atmosphere, and finally pulling down to a vacuum.
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