Replace double dimmer switch with single

24 Nov 2015
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United Kingdom

A room in my flat has a double dimmer switch but only one ceiling-mounted light (and no other main lights). It's also old and causing flickering (several of the other single dimmers in the flat have already been replaced because of this).

When I remove the switch from the wall there are two red and two black wires, one of each goes to different parts of the switch, i.e. one pair goes to the dimmer on the left and one pair to the dimmer on the right.

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The switches in the consumer unit aren't labelled but the 6A MCB on the left turns off the light.

Screenshot 2020-11-29 at 12.59.53.png

To change this dimmer switch in a safe way am I correct in thinking the cable needs to be disconnected at both ends? I've read elsewhere that only the cables by the dimmer switch need to be disconnected and put in a terminal block but surely that still leaves live wires behind the switch which doesn't sound right?




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Do you know where the other end is? Presumably at a (disused?) light somewhere.

In connector blocks will be fine. There are always live wires behind switches.

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