Is the problem the shower or the isolation switch

[stealthwolf]

We've bought our first house about two months ago. Everything's been fine up until today. The bathroom is fitted with an electric shower - Gainsborough 10.5se electric shower.

(I gather that this isn't a good company to go for looking at the search results).

Normally:
Having never had an electric shower before, normally I turn on the isolation supply via the pull cord in the bathroom. Then I press the button on the shower - hot water comes out. When I've finished, press the button and pull the cord so the isolation is off.

Today:
If I turn on the isolation switch via the pull cord, the light comes on. If I press the button for the shower, cold water comes out and the red light for isolation switch turns off. If I press the button for the shower to turn it off, the isolation switch light comes back on. The red light itself looks a bit dimmer than normal.

I don't know if the shower is causing problems, or if it's the isolation switch. How to do I progress from here?

 

[EFLImpudence]

Probably a loose connection - most likely in the pull switch which is a common occurrence but could be somewhere else.

 

[Iggifer]

My money is on the switch - loose neutral probably.

I would start with checking the tightness of the terminals in the switch (with the power off).

I went to a shower not working the other day, dropped the pull cord down and the supply live wasn't even screwed into the switch (had popped out) nice easy one!

You might find that having a loose neutral has burnt out part of the switch, if so you will need to replace and cut back the cable to an unburnt section

If you don't feel confident with any of that, it's time for an electrician, but if you do, make sure your terminals are as tight as you can get them without breaking anything

-Damnit, what 'e said

 

[flameport]

Gainsborough 10.5se electric shower. (I gather that this isn't a good company to go for looking at the search results).

There's nothing inherently wrong with them, however if anything goes wrong, the only repair is to replace the entire unit, individual parts are not available.

 

[PrenticeBoyofDerry]

It does sound like a loose connection, worth checking at isolator and fuse board.

 

[stealthwolf]

To update, I replaced the isolation switch. The shower works.

The problem I have is the old switch had two earth terminals - one for supply and one for appliance. The new switch has only one earth terminal and I've connected both in there. Is this safe?

Secondly, the appliance neutral was a bit blackened around the copper and sleeve areas. Was this the burnt out bit? Have now trimmed this back.

 

[flameport]

Earths - yes, this is fine.

The blackened part would have been the problem, a loose connection caused overheating.
Provided you have cut off the damaged wire, then this is ok.

 

[PrenticeBoyofDerry]

The problem I have is the old switch had two earth terminals - one for supply and one for appliance. The new switch has only one earth terminal and I've connected both in there. Is this safe?

Yes providing you have continuity of the earths and they are making good contact. When two earth terminals are present, they are still connected together, as there is a metal plate that links them.

Secondly, the appliance neutral was a bit blackened around the copper and sleeve areas. Was this the burnt out bit? Have now trimmed this back.

That will have been the reason for the fault, loose neutral arcing, you have done the right thing be striping the cable back to shiny copper.