Replacing Light Switch

29 Jul 2022
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United Kingdom
So I am trying to replace a 1 gang 1 way light switch. However, when I have taken off the faceplate of the old switch, there is only L1 and L2. There are two red wires connected to L1 and one red wire connected to L2.

On the new switch, there is L1, L2 and Com. I'm just a bit confused as to where these should go. Should it be the 2 red in L1 and the 1 in Com, or the other way around? Or the same as it was in the previous with just L1 and L2 in use?
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I am not an electrician...

I am guess that L1 in the old photo borrowed a live from elsewhere. I would check to see if L1 is perinatally live, and if yes, put the two wires in Com and the switched live in L1 on the new switch.
put the two wires into COM and the single wire into L2, I expect it will work. If it seems to be upside down, turn it over.

You can put the single wire into L1 instead if you want to.

next time Aldi or Lidl sell a multimeter at about £10, buy one.
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The 2 red in COM and 1 in L1 worked a treat. Thanks for your help and recommendations, I will certainly grab one for next time!

Thank you! :)

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