Sauber PAC-125773 Mode D'emploi page 33

INSTRUCTIONS FOR REPAIRING APPLIANCES CONTAINING R290
1. Servicing
1) Checks to the area
Prior to beginning work on systems containing flammable refrigerants, safety checks are necessary to ensure
that the risk of ignition is minimised. For repair to the refrigerating system, the following precautions shall be
complied with prior to conducting work on the system.
2) Work procedure
Work shall be undertaken under a controlled procedure so as to minimise the risk of a flammable gas or vapour
being present while the work is being performed.
3) General work area
All maintenance staff and others working in the local area shall be instructed on the nature of work being
carried out. Work in confined spaces shall be avoided. The area around the workspace shall be sectioned off.
Ensure that the conditions within the area have been made safe by control of flammable material.
4) 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. non-sparking, adequately sealed or intrinsically safe.
5) 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 CO₂ fire extinguisher adjacent to the
charging area.
6) No ignition sources
No person carrying out work in relation to a refrigeration system which involves exposing any pipe work that
contains or has contained flammable refrigerant shall use any sources of ignition in such a manner that it may
lead to the risk of fire or explosion. 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. Prior to work taking place, the area around the
equipment is to be surveyed to make sure that there are no flammable hazards or ignition risks. "No Smoking"
signs shall be displayed.
7) Ventilated area
Ensure that the area is in the open or that it is adequately ventilated before breaking into the system or
conducting any hot work. A degree of ventilation shall continue during the period that the work is carried out.
The ventilation should safely disperse any released refrigerant and preferably expel it externally into the
atmosphere.
8) Checks to the refrigeration equipment
Where electrical components are being changed, they shall be fit for the purpose and to the correct
specification. At all times the manufacturer's maintenance and service guidelines shall be followed. If in doubt
consult the manufacturer's technical department for assistance.
The following checks shall be applied to installations using flammable refrigerants:
– The charge size is in accordance with the room size within which the refrigerant containing parts are
installed;
– The ventilation machinery and outlets are operating adequately and are not obstructed;
– If an indirect refrigerating circuit is being used, the secondary circuit shall be checked for the presence of
refrigerant;
– 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
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