Sinclair SDV 6 Service Manual page 7

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.
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.
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 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 manufacturer's specifications.
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.
Check that cabling will not be subject to wear, corrosion, excessive pressure, vibration, sharp edges or any other adverse
environmental effects. The check shall also take into account the effects of ageing or continual vibration from sources
such as compressors or fans.
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.
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