Shower switch went bang

[james2006]

Hi - does anyone have any idea on the following ?

I was renovating the bathroom and when doing so got an electric shower to put in an electric shower. An electrician installed the shower on 10mm wire, 40a rcbo, 45a switch and the shower is 9.5 kw. I have the work fully certified. The shower has been great for 5 months and then this week the following happened.

1) turned the shower off at the shower and the tripper blew, smelt smoke from the switch so checked and hot. Noted slight nic out of the neutral insulation so repaired with shrink tube. Fitted new switch and shower work fine again for a day or two.
2) then I turned the switch on the wall on today(when shower was off) and bang. The switch on the wall violently sparked and it was that bad the switch broke and was was burned.

Any thoughts on the issue? I was thinking maybe a short on the cable from the switch to the shower or maybe a short on the shower ??

 

[streetlighter]

Probably a loose connection inside the shower switch cause the excessive heat build up and the switch to fail.
Avoid cheap no name shower pull cords invest in a good quality one i tend to like the Crabtree very easy to wire compared to the traditional ones.

 

[kevindgas]

similarly i tend to use the 50A round switch rather than the 45A square ones as they seem a little more robust.

 

[james2006]

Thanks guys. Would it make sense that the shower has gone through 2 switches in a couple of days?

 

[streetlighter]

I would get the electrician back who installed the switch to rectify the fault. Thats why i only use good quality parts on my jobs learned from experience that cheap parts mean go backs and unhappy clients.

 

[ban-all-sheds]

similarly i tend to use the 50A round switch rather than the 45A square ones as they seem a little more robust.

Or a regular light switch to work a nice chunky contactor installed in a nice roomy box in the loft.