Cord switch red light is dim

[Cohen]

I have a cord switch to isolate power to an electric shower in my bathroom. Recently, the red light on the cord switch box has become very dim when put into the on position. The shower itself will not operate. I have checked the fuse box and nothing has been tripped.

Is the problem with the cord switch or the electric shower?


If it helps, here is what it normally like before it stopped working:

Cord switch on = strong red light = amber standby light on electric shower

Currently:

Cord switch on = dim red light = no standby light on electric shower

 

[rebuke]

If you're sure nothings tripped in the CU, then the most likely cause is either a failed pull cord switch, or possibly just a bad termination in it. If you're happy to do it, then isolate the power to the shower circuit at the CU, open the pull switch, test to ensure it's isolated etc, then see if there are any signs of loose connections etc. If not, then try just replacing the switch...

 

[JohnD]

I would stronly suspect a poor connection. Very likely the neutral wire was loose and overheated.

If so, heat-damaged copper is softened and can't be used again - you may have to replace the switch and cut away the damaged copper wire to a clean bright end.

With these larger conductors it is worth checking the tightness of the screws (be sure to use the correct driver) a few hours after you tightened them, and then again after a few days. The metals squash to shape a bit under pressure so you can often retighten them a bit after giving them time to settle. If they are at all loose they will overheat and get looser and looser until they burn away.

It is most common in shower switches because they carry high sustaioned loads. Doing up the screws while up a stepladder and your head is pressed against the ceiling doesn't help either.