electric shower causes lights to dim

[toshtastic]

hi,

I have an electric shower installed in my house (fitted before I moved in) and when I have two issues with it :

1) the light on the main power switch to the shower is always lit, even if the shower is off. Is this serious? anyone know why it does this?

2) when I turn the actual shower on (i.e. start the water) then the lights in my house dim. Is this serious or just that the shower needs that power to start up? Its a 10kw shower

For info my house is a semi detached bungalow

Thanks

T

 

[securespark]

10 K's is a lot of juice and on start-up, there is a big draw which often makes the lights flicker.

The light on the main power switch is always lit even if the shower is off....

The light (neon) on the shower isolator should light when the switch is closed. Switching the shower unit on & off at the unit will have no effect on the neon on the switch.

If you mean the neon on the switch stays on even when the switch is off, it is wired the wrong way round.

 

[toshtastic]

yeah I meant the neon light is always on - cool Ill have a look at that. Thanks

so you think that the lights dimming is ok? I dont have anything to worry about with the dimming then?

would a less powerful shower make a difference?

 

[toshtastic]

Ps the lights dont actually flicker - they dim and stay dimmed until I turn the water off.

 

[sparkyspike]

Dimming lights can be caused by a cable which is too small, or by a bad connection - both of which can lower the voltage. Do you know if your shower cable is big enough -i.e. at least 10mm. Or if it has a long run from the fusebox?

 

[RF Lighting]

Have a google for 'volts drop' and all should become clear...

 

[toshtastic]

it cant be that far from the fuse box as Im only in a bungalow and my fuse box itself is probably about 2m from the shower.

Im not 100% sure how thick the shower cable is but I will look and find out

Is it easy enough to change the cable?

Thanks

 

[sparky1scotland]

I would stick in a 10mm cable, cant go wrong with that !! Best way to find out the cable is to go to B&Q and get a very small cutting !!!! or check the measurements !!! 2m shouldnt give you voltage drop. To replace the cable will only be as easy as you make it. Remember that the cable must be protected with a metal plate if buried in plaster below 45mm !! if its cavity then your fine !

 

[securespark]

Remember that the cable must be protected with a metal plate if buried in plaster below 45mm !! if its cavity then your fine !

Can you be a bit more accurate??

 

[ban-all-sheds]

If the shower cable is too small it will cause voltage drop problems for the shower and could overheat, but it can't have anything to do with the lights dimming. If anything it would make that problem less severe because it would increase the resistance of the load and thus lower the current.

If the lights go dim it's because the overall load is too big for the installation, or the shower is too big a load for the CU, or there's a loose connection in the CU or upstream of it.

tosh - could you post a picture of the CU, and the tails running to and from the meter?

And if you aren't confident about checking things inside a CU (parts of it will be live) then you'll probably need to get an electrician.

 

[sparky1scotland]

It was in relation to the cable runnig to the shower unit, if the already installed cable had been raggled into the wall then the replacement 10mm would require a metal protective cover if and only if the cable was not buried more than 45mm or is it 50mm ??? according to the regs !!

 

[ban-all-sheds]

So you've been to his house and seen that the cable doesn't run in recognised zones have you?

And what's with all the exclamation marks?

45mm or is it 50mm

You should know that, being a sparky...

 

[sparky1scotland]

Oh you are cheeky eh !!!! yeah more exclamation marks, not been to his house yet but open to homers !!!! and I do know, was just wondering if you did !!!!!! and if your into sheds why you on ere ???? oops question marks now does that mean you really hate me ??????

 

[ban-all-sheds]

No - it just means I'm more convinced that you're a tw@.

 

[sparky1scotland]

well done pal, its people like you that make people turn away from these forums !!! get a life, sad individual !!!!!!!!!!!!!!!!