Page 15 - Manual - Mobile Air Conditioner G21 - Envi 12H

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
Initial safety checks shall include:
• that capacitors are discharged: this shall be done in a safe manner to avoid possibility of spar-
king;
• that 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
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 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.
11. Repair to 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.
Replace components only with parts specified by the manufacturer. Other parts may result in the
ignition of refrigerant in the atmosphere from a leak.
12. Cabling
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 aging or continual vibration from sources such as compressors or fans.
13. Detection of flammable refrigerants
Under no circumstances shall potential sources of ignition be used in the searching for or detection
of refrigerant leaks. A halide torch (or any other detector using a naked flame) shall not be used.
14. Removal and evacuation
When breaking into the refrigerant circuit to make repairs – or for any other purpose – conventional
procedures shall be used. However, for flammable refrigerants it is important that best practice is
followed since flammability is a consideration. The following procedure shall be adhered to:
• remove refrigerant;
• purge the circuit with inert gas;
• evacuate;
• purge with inert gas;
• open the circuit by cutting or brazing.
The refrigerant charge shall be recovered into the correct recovery cylinders. For appliances