13 INFORMATION 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
minimized. For repair to the refrigerating system, the following precautions shall be complied with prior to conducting work on the system.
2) Work procedure
Works 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 sapces
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.
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.
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 power or CO
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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’s 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 HVAC 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 circuits shall be checked for the presence of refrigerant; marking to the
equipment continues to be visible and legible.
• Marking 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.
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, and 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:
• That capacitors are discharged: this shall be done in a safe manner to avoid possibility of sparking;
• That there no live electrical components and wiring are exposed while charging, recovering or purging the system;
• That there is continuity of earth bonding.
10) Repairs to sealed components
a) During repairs to sealed components, all electrical supplies shall be disconnected from the equipment being worked upon prior to any
removal of sealed covers, etc. If it is absolutely necessary to have an electrical supply to equipment during servicing, then a permanently
operating form of leak detection shall be located at the most critical point to warn of a potentially hazardous situation.
b) 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 manufacture's specifications.
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Summary of Contents for DA-HP-16-230
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