4
Area ventilation
•
Prior to penetrating the unit in any way to perform any required service, ensure
that the area is open and adequately ventilated. Proper ventilation, to allow for
safe dispersion of any refrigerant which may be inadvertently released to the
atmosphere, should be maintained while service is being performed on the unit.
Refrigeration equipment check
• The manufacturer’s service and maintenance guidelines must be followed at all
times. When replacing any electrical components, be sure to use only components
which are of the same type and rating and which are recommended/approved by
the manufacturer. If in doubt, consult the manufacturer’s technical department
for assistance.
•
The following checks shall be applied to installations using flammable refrigerants:
-
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;
-
refrigerating 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.
Electrical component check
•
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:
-
that capacitors are discharged: this shall be done in a safe manner to avoid
possibility of sparking;
-that no live electrical components and wiring are exposed while charging,
recovering or purging the system;
-
that there is continuity of earth bonding.
Repair of insulated components
• 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.
•
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 the apparatus is mounted securely.
•
Ensure that seals or sealing materials have not degraded to the point 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.
Repair of 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.
