My only thought of caution when it comes to electrical appliance repairs is that some of the safety features in the original design & assembly can sometimes be very subtle. I vaguely recall a Television magazine article many moons ago that discussed a couple of blobs of glue on the back of the main on/off switch of a certain model of TV (this is back in the days when TVs had a simple mechanical DP switch) - IIRC it turned out that the glue was part of means of providing protection against electric shock - even if the wire came adrift from the switch terminal, the glue prevented it moving and potentially coming into contact with the ELV circuitry (which is then exposed to touch via the aerial & headphone sockets etc). That might be an extreme example, but certainly there are many cases where a cable tie or bit of sleeving or even the precise length or positioning of a wire are critical to maintaining double insulation. And of course errors in such things are never going to show up on a 'portable appliance test'.

So as some of the techniques used inside appliances can be unknown or easily overlooked by those, for example, more used to say BS 7671 style installation work, some particular care might be needed in deciding on who is 'competent' (electrically).

   - Andy.

My only thought of caution when it comes to electrical appliance repairs is that some of the safety features in the original design & assembly can sometimes be very subtle. I vaguely recall a Television magazine article many moons ago that discussed a couple of blobs of glue on the back of the main on/off switch of a certain model of TV (this is back in the days when TVs had a simple mechanical DP switch) - IIRC it turned out that the glue was part of means of providing protection against electric shock - even if the wire came adrift from the switch terminal, the glue prevented it moving and potentially coming into contact with the ELV circuitry (which is then exposed to touch via the aerial & headphone sockets etc). That might be an extreme example, but certainly there are many cases where a cable tie or bit of sleeving or even the precise length or positioning of a wire are critical to maintaining double insulation. And of course errors in such things are never going to show up on a 'portable appliance test'.

So as some of the techniques used inside appliances can be unknown or easily overlooked by those, for example, more used to say BS 7671 style installation work, some particular care might be needed in deciding on who is 'competent' (electrically).

   - Andy.