Midea MOAB30-09HFN8-QRD0GW, Service Manual

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Safety Precautions 3
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2. Information servicing(For
flammable materials)
2.1 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 minimized.
• For repair to the refrigerating system, the following
precautions shall be complied with prior to conducting work
on the system.
2.2 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.
2.3 Work procedure
• 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 work space shall be sectioned off.
Ensure that the conditions within the area have been made
safe by control of flammable material.
2.4 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. no sparking,
adequately sealed or intrinsically safe.
2.5 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.
2.6 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.
2.7 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.
2.8 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 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.
2.9 Checks to electrical devices
• Repair and maintenance to electrical components shall
include initial safety checks and component inspection
procedures. If a fault exists that could compromise
safety, then no electrical supply shall be connected to
the circuit until it is satisfactorily dealt with. If the fault
cannot be corrected immediately but it is necessary to
continue operation, an adequate temporary solution
shall be used. This shall be reported to the owner of
the equipment so all parties are advised. Initial safety
checks shall include: